Visionappx

Supplementary appendix This appendix formed part of the original submission and has been peer reviewed.

We post it as supplied by the authors.

Supplement to: Bourne RRA, Flaxman SR, Braithwaite T, et al, on behalf of the Vision Loss Expert Group. Magnitude, temporal trends, and projections of the global prevalence of blindness and distance and near vision impairment: a systematic review and meta-analysis. Lancet Glob Health 2017; published online Aug 2. http://dx.doi. org/10.1016/S2214-109X(17)30293-0.

Text 1. Definitions and analytic framework We estimate the prevalence of vision loss for the period 1990-2020 by age, sex, and year in 187 countries (Table 1), for the following extended vision loss categories: • Blind: < 3/60 and/or a visual field of no greater than 10◦ in radius around central fixation • Severe vision loss: < 6/60 and ≥ 3/60 • Moderate vision loss: < 6/18 and ≥ 6/60 • Mild vision loss: < 6/12 and ≥ 6/18 These estimates are derived, following Stevens and colleagues 9 , from two separate models for the following core levels of vision impairment: • Blind: < 3/60 and/or a visual field of no greater than 10◦ in radius around central fixation • MSVI: < 6/18 and ≥ 3/60 Our study was carried out in five steps: • Data identification and access • Conversion of vision impairment data to two core severity levels for modeling, blindness and MSVI • Application of an age pattern to data which are not presented by age • Development of a hierarchical model to estimate prevalence of two core levels of vision impairment • Conversion of vision impairment data from two core levels to four extended severity levels

Text 2. Data identification and access We used data from epidemiologic studies and surveys which we collected to update a previously published systematic review 1 . Following Bourne and colleagues 1 , we identified studies or surveys fulfilling the following inclusion criteria: • The studies reported prevalence of vision impairment from cross-sectional surveys of representative populations of a country or area of a country.

• The definitions of vision impairment were clearly stated, using thresholds of visual acuity in the better eye that matched the extended definitions of vision impairment.

• Best corrected and/or presenting visual acuity was given.

• The procedures used for measurement of visual acuity were clearly stated.

The authors carried out a systematic review of the literature for distance vision impairment data. They also obtained unpublished data sources. Distance visual acuity data was used from 288 studies; 270 reported or could be used to estimate the prevalence of blindness and 245 reported or could be used to estimate the prevalence of MSVI. Both blindness and MSVI data were used to estimate mild vision impairment, meaning that all 288 studies were used for the estimates of mild vision impairment. Data used in this analysis are listed in Table 2. 18 studies were used to estimate presbyopia, as shown in Table 3. The current systematic review of distance visual acuity data sources used the same search terms of a systematic review published previously, 6 but extended the review to include more recently published studies up to July 2014. The methodology for this systematic review extension is described in Figure 9 as a PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flowchart with a PRISMA checklist in Table 9.

The Search Strategy for the Systematic Review is described in the following sections: • 2.1 Developing the Search Strategy (distance visual acuity data sources) • 2.2 Final Search Strategies (distance visual acuity data sources) • 2.3 Results & Discussion (distance visual acuity data sources) • 2.4 Systematic review of studies of presbyopia prevalence

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Text 2.1. Developing the Search Strategy (distance visual acuity data sources) The search strategy was required to capture epidemiological studies of vision loss and blindness. The search excluded animal studies.

This report describes update searches undertaken for the Global Vision Database project in July 2014. These searches update the original search undertaken in 2008 and the subsequent searches run in 2012 and 2013.

Several approaches to capturing the search concepts were developed and tested out in Ovid MEDLINE. The objective was to achieve a focused strategy that would identify epidemiological studies of blindness. The strategy needed to balance adequate sensitivity (not missing too many relevant records) against reasonable precision (not producing high proportions of irrelevant records) bearing in mind the resource available to process the records produced by the searches. To achieve this balance required the use, in a master strategy for MEDLINE, of the various indexing options that were available. The strategy also had to take account of variability in the way authors describe their research and indexers index research with Medical Subject Headings (MeSH). In an ideal world we would expect all records about the epidemiology of blindness to be indexed with the MeSH and appropriate subheading, for example BLINDNESS/ep. In practice, however, there are many records about that topic that are not indexed in that way.

The strategy takes account of such variability in indexing approaches. The strategy also had to account for the fact that the search would be undertaken in both indexed and unindexed records (e.g. MEDLINE In Process records) so had to search for text words (in the title and abstract) as well as MeSH. As well as the concept of the epidemiology of blindness, the strategy had to retrieve studies about the epidemiology of selected specific eye diseases which might result in blindness or visual impairment.

After several iterations, checking the impact of changes at each stage, a strategy with three elements was agreed as follows for Ovid MEDLINE (see also Box 1).

Element 1 A search on the concepts of blindness and visual impairment linked to epidemiological terms through three approaches: 1. Precoordination of a MeSH blindness/visual impairment term with its epidemiology subheading, e.g. exp blindness/ep 2. Searching for the occurrence of a MeSH blindness/visual impairment term along with the occurrence of an epidemiological MeSH term in the same record, e.g. exp blindness/ and (incidence/ or prevalence/ or mortality/ or morbidity/) 3. Searching for the occurrence of a MeSH blindness/visual impairment term and an epidemiological concept expressed as a text word in the title or abstract of a record, e.g. exp blindness/ and (epidemiology or incidence or prevalence or mortality).ti,ab.

Element 2 A search for specific eye diseases linked to epidemiological terms and also to terms indicating blindness using the following approaches: 1. Precoordination of a MeSH eye disease heading with the epidemiology subheading and then looking for the occurrence of that combination in the same record as one where blindness/visual impairment is a term in the title or abstract, e.g.

• conjunctival diseases/ep • exp blindness/ or (blindness or (visual adj3 impair$) or (vision adj3 impair$)).ti,ab.

• 1 and 2 2. Searching for the occurrence of a MeSH eye disease heading in the same record as an epidemiological MeSH heading and as blindness/visual impairment as a term in the title or abstract, e.g.

• conjunctival diseases/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/) • exp blindness/ or (blindness or (visual adj3 impair$) or (vision adj3 impair$)).ti,ab.

• 1 and 2 3. Searching for the occurrence of eye disease text words in close proximity to epidemiology text words in the title and abstract of records, in the same records as blindness MeSH or blindness/visual impairment text words, e.g.

• (retinitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab.

• exp blindness/ or (blindness or (visual adj3 impair$) or (vision adj3 impair$)).ti,ab.

• 1 and 2 2

Element 3 Searching for records that specifically mention population-based eye surveys using a range of synonyms for that concept in the title and abstract, e.g. (population adj3 eye adj3 survey$).ti,ab.

To improve the precision of the search a range of limits and their effects on the numbers of records retrieved were explored: • Removing studies about animals by using a safe exclusion approach: Result set NOT (animals/ NOT humans/) This approach excludes records which have are coded solely as Animal studies but retains those that are also indexed as Human studies (i.e. have Animals/ as well as Humans/ in the subject indexing). This is an improvement on searching specifically for Human studies because not all records involving human subjects are coded with the MeSH Humans/ • Excluding letters coded in the MEDLINE Publication Type field; • Excluding comments coded in the MEDLINE Publication Type field; • Excluding editorials coded in the MEDLINE Publication Type field; • Excluding clinical trials coded in the MEDLINE Publication Type field; • Excluding reviews coded in the MEDLINE Publication Type field or as a text word in the title.

The search strategy was also combined with search terms to retrieve records from specific countries. A country listing was provided. Following queries some revisions to the list were made. Israel did not receive a country grouping at that stage.

Once agreed the MEDLINE strategy was translated appropriately for EMBASE. The search strategy was adapted to run in WHOLIS. WHOLIS uses MeSH for indexing, but, following careful reading of the Help file, does not seem to offer explosions. The Help file seems to indicate that MeSH terms are included in a words and phrases search and that parentheses and Boolean operators can be used within a search string. Based on this assessment selected terms were searched for as words and phrases. The strategy was adapted to be sensitive.

The following databases were searched: • Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations and Ovid MEDLINE(R) 1946 to Present (updated daily); • Ovid Embase 1974 to 2014 July 07; • WHOLIS library catalogue (http://dosei.who.int/uhtbin/webcat).

Records added to the databases, indexed or otherwise revised since June 2013 were identified using various update codes relevant to the specific databases. The search results were not downloaded by country, but in a single large set.

The results were deduplicated against each other and the results of the 2008, 2012 and 2013 searches.

Records were loaded into Endnote bibliographic software as a series of country group specific databases. The WHOLIS records were loaded into a single separate Endnote database.

Records were deduplicated. Animal studies were deleted as they were identified. Records which appeared in the incorrect country group were moved into their relevant country database. Records in the miscellaneous database whose country of focus could be easily identified were moved into their relevant country database.

Text 2.2. Final Search Strategies (distance visual acuity data sources) The final search strategies and results are shown below.

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Box 1. Key to Ovid MEDLINE search syntax Exp .ti,ab. / /ep And Or adj3 $

Explodes a MeSH to capture more specific MeSH Searches for a word in the title and abstract of a record Indicates that the search term is a Medical Subject Heading (MeSH) Searches for a subheading linked to a MeSH, in this case epidemiology Achieves a Boolean AND combination Achieves a Boolean OR combination Adjacency operator, searches for words up to 3 words apart Truncation operator, searches for words beginning with the stem, e.g. impair$ retrieves impair, impairment, impairments, impaired, impairing and impairs

2.2.1 Medline Search Database: Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations and Ovid MEDLINE(R) 1946 to Present. Searched 08/07/14

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exp blindness/ep or exp blindness/mo (2033) exp blindness/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (1183) exp blindness/ and (age distribution/ or sex distribution/) (323) exp blindness/ and exp eye diseases/ep (2387) exp blindness/ and (epidemiology or incidence or prevalence or mortality).ti,ab. (1733) (blindness and (epidemiology or incidence or prevalence or mortality)).ti,ab. (3134) vision/ep or vision/mo (0) vision/ and (age distribution/ or sex distribution/) (13) (vision and (epidemiology or incidence or prevalence or mortality)).ti,ab. (4955) vision/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (70) exp visual acuity/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (2237) exp visual acuity/ and (age distribution/ or sex distribution/) (594) (visual acuity and (epidemiology or incidence or prevalence or mortality)).ti,ab. (4104) vision, binocular/ and (incidence/ or prevalence/ or morbidity/ or mortality/) (68) vision, binocular/ and (age distribution/ or sex distribution/) (23) ((vision adj3 binocular) and (epidemiology or incidence or prevalence or mortality)).ti,ab. (119) Vision, Low/ep or vision, low/mo (480) vision, low/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (366) vision, low/ and (age distribution/ or sex distribution/) (154) (low vision and (epidemiology or incidence or prevalence or mortality)).ti,ab. (364) Night Blindness/ep or night blindness/mo (93) night blindness/ and (incidence/ or prevalence/ or morbidity/ or mortality/) (58) night blindness/ and (age distribution/ or sex distribution/) (7) Presbyopia/ep or presbyopia/mo (69) presbyopia/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (39) presbyopia/ and (age distribution/ or sex distribution/) (18) (presbyopi$ and (epidemiology or incidence or prevalence or morbidity)).ti,ab. (84) Visually Impaired Persons/ and (incidence/ or prevalence/ or morbidity/ or mortality/) (343) visually impaired persons/ and (age distribution/ or sex distribution/) (118) (visual$ adj3 impair$ adj3 (incidence or prevalence or epidemiolog$ or morbidity)).ti,ab. (406) (vision adj3 impair$ adj3 (incidence or prevalence or epidemiolog$ or morbidity)).ti,ab. (65) ((amaurosis or deaf-blind) adj3 (incidence or prevalence or epidemiolog$ or morbidity)).ti,ab. (10) conjunctival diseases/ep or conjunctival diseases/mo (115)

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conjunctival diseases/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (101) conjunctivitis/ep, mo (461) conjunctivitis/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (135) ((conjunctivitis or conjunctival) adj3 (incidence or prevalence or epidemiolog$ or mortality)).ti,ab. (216) ophthalmia neonatorum/ep, mo (76) ophthalmia neonatorum/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (14) (ophthalmia neonatorum adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (10) trachoma/ep, mo (962) trachoma/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (366) (trachoma adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (348) pterygium/ep, mo (142) pterygium/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (88) (pterygium adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (68) xerophthalmia/ep, mo (225) xerophthalmia/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (107) (xerophthalmia adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (75) corneal diseases/ep, mo or (corneal diseases/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (434) (corneal adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (15) corneal opacity/ep, mo or (corneal opacity/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (113) (cornea$1 adj3 (opaque$ or opac$) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (25) keratitis/ep, mo or (keratitis/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (362) (keratitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (161) corneal ulcer/ep, mo or (corneal ulcer/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (301) (cornea$ adj3 ulcer$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (40) keratoconus/ep, mo or (keratoconus/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (145) (keratoconus adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (47) eye diseases, hereditary/ep, mo or (eye diseases, hereditary/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (54) (hereditary adj3 eye adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (0) retinitis pigmentosa/ep, mo or (retinitis pigmentosa/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (208) (retinitis pigmentosa adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (33) exp eye infections/ep, mo or (exp eye infections/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (3700) (infection$ adj3 eye$1 adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (11) lens diseases/ep, mo or (lens diseases/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (68) (lens adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (3) exp aphakia/ep, mo or (exp aphakia/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (92) (aphakia adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (12) cataract/ep, mo or (cataract/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (2347) (cataract$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (938) ocular hypertension/ep, mo or (ocular hypertension/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (315) ((ocular or intraocular) adj hypertens$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (54) glaucoma/ep, mo or (glaucoma/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (1451) glaucoma, angle-closure/ep, mo or (glaucoma, angle-closure/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (256) glaucoma, open-angle/ep, mo or (glaucoma, open-angle/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (815) (glaucoma adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (611) optic nerve diseases/ep, mo or (optic nerve diseases/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (294) (optic nerve adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (51) exp optic atrophy/ep, mo or (exp optic atrophy/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (217) (optic atrophy adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (18) refractive errors/ep, mo or (refractive errors/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (899) (refractive error$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (250) astigmatism/ep, mo or (astigmatism/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (342) (astigmatism adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (152) hyperopia/ep, mo or (hyperopia/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (220)

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(hyperopia adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (80) exp myopia/ep, mo or (exp myopia/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (1009) ((myopia or myopic) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (485) retinal diseases/ep, mo or (retinal diseases/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (687) (retina$1 adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (21) diabetic retinopathy/ep, mo or (diabetic retinopathy/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (2468) (diabetic retinopath$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (466) retinal degeneration/ep, mo or (retinal degeneration/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (142) (retina$1 adj3 degenerat$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (20) exp macular degeneration/ep, mo or (exp macular degeneration/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (1499) (macular adj3 degenerat$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (55) retinal detachment/ep, mo or (retinal detachment/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (625) (retina$1 adj3 detach$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (285) retinal vein occlusion/ep, mo or (retinal vein occlusion/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (214) (retina$1 adj3 vein adj3 occlu$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (29) retinitis/ep, mo or (retinitis/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (79) (retinitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (117) chorioretinitis/ep, mo or (chorioretinitis/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (82) (chorioretinitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (9) cytomegalovirus retinitis/ep, mo or (cytomegalovirus retinitis/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (183) retinopathy of prematurity/ep, mo or (retinopathy of prematurity/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (766) (retinopathy adj3 prematurity adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (202) exp choroid diseases/ep, mo or (exp choroid diseases/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (703) (choroid adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (0) exp uveitis/ep, mo or (exp uveitis/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (1455) (uveitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (170) vision disorders/ep, mo or (vision disorders/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (2158) amblyopia/ep, mo or (amblyopia/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/)) (353) (amblyopia adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (174) (population adj3 eye adj3 survey$).ti,ab. (25) (population adj3 vision adj3 survey$).ti,ab. (1) (population adj3 blindness adj3 survey$).ti,ab. (13) (population adj3 visual adj3 survey$).ti,ab. (1) animals/ not humans/ (3873264) (letter or comment or editorial).pt. (1346697) (clinical trial or controlled clinical trial).pt. (506859) randomized controlled trial.pt. (378334) review.pt. (1901065) exp blindness/ or (blindness or (visual adj3 impair$) or (vision adj3 impair$)).ti,ab. (42228) or/1-32 (13006) or/33-115 (22051) or/116-119 (40) 126 or (127 and 125) or 128 (13789) 129 not (120 or 121 or 122 or 123 or 124) (10647) 130 and (2013$ or 2014$).ed,ep,dc,dp. (1407) remove duplicates from 131 (1336)

2.2.2 EMBASE Search Database: Embase Ovid SP ÂĄ1974 to 2014 July 07Âż Searched 08/07/14 1 2

exp blindness/ep (1710) exp blindness/ and (prevalence/ or incidence/ or morbidity/ or mortality/) (2928)

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exp blindness/ and (age distribution/ or sex ratio/) (391) exp blindness/ and exp eye disease/ep (2526) exp blindness/ and (epidemiology or incidence or prevalence or mortality).ti,ab. (3354) (blindness and (incidence or prevalence or epidemiology or mortality)).ti,ab. (3772) vision/ and (age distribution/ or sex ratio/) (312) (vision and (epidemiology or incidence or prevalence or mortality)).ti,ab. (6676) vision/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (812) exp visual acuity/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (3323) exp visual acuity/ and (age distribution/ or sex ratio/) (921) (visual acuity and (epidemiology or incidence or prevalence or mortality)).ti,ab. (4736) binocular vision/ and (incidence/ or prevalence/ or morbidity/ or mortality/) (121) binocular vision/ and (age distribution/ or sex ratio/) (35) ((vision adj3 binocular) and (epidemiology or incidence or prevalence or mortality)).ti,ab. (127) visual disorder/ep (923) visual disorder/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (1783) visual disorder/ and (age distribution/ or sex ratio/) (285) (low vision and (epidemiology or incidence or prevalence or mortality)).ti,ab. (421) night blindness/ep (68) night blindness/ and (incidence/ or prevalence/ or morbidity/ or mortality/) (150) night blindness/ and (age distribution/ or sex ratio/) (13) presbyopia/ep (45) presbyopia/ and (incidence/ or prevalence/ or mortality/ or morbidity/) (64) presbyopia/ and (age distribution/ or sex ratio/) (30) (presbyopi$ and (epidemiology or incidence or prevalence or morbidity)).ti,ab. (87) (visual$ adj3 impair$).ti,ab. and (incidence/ or prevalence/ or morbidity/ or mortality/) (1643) (visual$ adj3 impair$).ti,ab. and (age distribution/ or sex ratio/) (324) (visual$ adj3 impair$ adj3 (incidence or prevalence or epidemiolog$ or morbidity)).ti,ab. (449) (vision adj3 impair$ adj3 (incidence or prevalence or epidemiolog$ or morbidity)).ti,ab. (75) ((amaurosis or deaf-blind) adj3 (incidence or prevalence or epidemiolog$ or morbidity)).ti,ab. (9) conjunctiva disease/ep (75) conjunctiva disease/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (230) conjunctivitis/ep (514) conjunctivitis/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (1069) ((conjunctivitis or conjunctival) adj3 (incidence or prevalence or epidemiolog$ or mortality)).ti,ab. (237) newborn ophthalmia/ep (66) newborn ophthalmia/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (57) (ophthalmia adj3 (neonat$ or newborn) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (12) trachoma/ep (867) trachoma/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (615) (trachoma adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (345) pterygium/ep (148) pterygium/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (194) (pterygium adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (87) xerophthalmia/ep (176) xerophthalmia/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (233) (xerophthalmia adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (79) cornea disease/ep (162) cornea disease/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (386) (cornea$ adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (13) cornea opacity/ep (59) cornea opacity/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (261) (cornea$ adj3 (opaque$ or opac$) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (26) keratitis/ep (338)

8

56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108

keratitis/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (554) (keratitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (185) cornea ulcer/ep (147) cornea ulcer/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (235) (cornea$ adj3 ulcer$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (52) keratoconus/ep (88) keratoconus/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (221) (keratoconus adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (54) (hereditary adj3 eye).ti,ab. and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (6) (hereditary adj3 eye adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (0) retinitis pigmentosa/ep (140) retinitis pigmentosa/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (228) (retinitis pigmentosa adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (36) exp eye infection/ep (1488) exp eye infection/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (1487) (infection$ adj3 eye$1 adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (12) lens disease/ep (33) lens disease/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (82) (lens adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (3) exp aphakia/ep (39) exp aphakia/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (195) (aphakia adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (12) exp cataract/ep (1674) exp cataract/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (3557) (cataract$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (1070) exp glaucoma/ep (1797) exp glaucoma/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (3366) (glaucoma adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (724) ((ocular hypertens$ or intraocular hypertens$) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (64) optic nerve disease/ep (198) optic nerve disease/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (670) (optic nerve adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (57) exp optic nerve atrophy/ep (166) exp optic nerve atrophy/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (420) (optic adj3 atroph$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (27) refraction error/ep (641) refraction error/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (1203) (refract$ adj3 error$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (288) astigmatism/ep (265) astigmatism/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (535) (astigmatism adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (169) hypermetropia/ep (217) hypermetropia/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (526) ((hyperopia or hypermetropia) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (96) exp myopia/ep (694) exp myopia/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (1234) ((myopia or myopic) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (546) retina disease/ep (183) retina disease/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (419) (retina$1 adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (26) diabetic retinopathy/ep (1523) diabetic retinopathy/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (3364) (diabetic retinopath$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (577)

9

109 retina degeneration/ep (79) 110 retina degeneration/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (138) 111 (retina$1 adj3 degenerat$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (24) 112 exp retina maculopathy/ep (1130) 113 exp retina maculopathy/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (2630) 114 (macular adj3 degenerat$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (65) 115 retina detachment/ep (291) 116 retina detachment/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (908) 117 (retina$1 adj3 detach$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (313) 118 exp retina vein occlusion/ep (135) 119 exp retina vein occlusion/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (361) 120 (retina$1 adj3 vein adj3 occlu$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (37) 121 exp retinitis/ep (622) 122 exp retinitis/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (1468) 123 (retinitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (115) 124 (chorioretinitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (9) 125 retrolental fibroplasia/ep (462) 126 retrolental fibroplasia/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (885) 127 (((retinopathy adj3 prematurity) or retrolental fibroplasia) adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (252) 128 exp choroid disease/ep (347) 129 exp choroid disease/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (1098) 130 (choroid adj3 disease$ adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (0) 131 exp uveitis/ep (1122) 132 exp uveitis/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (2482) 133 (uveitis adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (237) 134 visual disorder/ep (923) 135 visual disorder/ and (incidence/ or prevalence/ or age distribution/ or sex ratio/ or morbidity/ or mortality/) (1950) 136 amblyopia/ep (286) 137 amblyopia/ and (incidence/ or prevalence/ or age distribution/ or sex distribution/ or morbidity/ or mortality/) (503) 138 (amblyopia adj3 (incidence or prevalence or epidemiology or mortality)).ti,ab. (203) 139 (population adj3 eye adj3 survey$).ti,ab. (27) 140 (population adj3 vision adj3 survey$).ti,ab. (1) 141 (population adj3 blindness adj3 survey$).ti,ab. (16) 142 (population adj3 visual adj3 survey$).ti,ab. (2) 143 or/1-31 (20344) 144 or/32-138 (30562) 145 exp blindness/ or (blindness or (visual adj3 impair$) or (vision adj3 impair$)).ti,ab. (54343) 146 144 and 145 (4309) 147 143 or 146 or (or/139-142) (20703) 148 limit 147 to (amphibia or ape or bird or cat or cattle or chicken or dog or "ducks and geese" or fish or "frogs and toads" or goat or guinea pig or "hamsters and gerbils" or horse or monkey or mouse or "pigeons and doves" or "rabbits and hares" or rat or reptile or sheep or swine) (422) 149 limit 147 to animal studies (256) 150 limit 147 to animals (392) 151 limit 147 to human (18835) 152 (148 or 149 or 150) not 151 (417) 153 147 not 152 (20286) 154 (letter or editorial or review).pt. (3262505) 155 153 not 154 (16520) 156 155 and (2013$ or 2014$).dd,em,dp. (2556) 157 remove duplicates from 156 (2539)

2.2.3. WHOLIS Search For the update search in June 2014, a series of individual searches was undertaken. All searches were limited to 2013-2014.

WHOLIS searches (2014) Search string words or phrase ”blindness” OR words or phrase ”visual” OR words or phrase ”vision” OR words or phrase ”acuity” OR words or phrase ”amaurosis” words or phrase ”conjunctiv$” OR words or phrase ”ophthalmia” OR words or phrase ”trachoma” OR words or phrase ”pterygium” OR words or phrase ”xerophthalmia” Words or phrase ”cornea$” OR words or phrase ”keratitis OR words or phrase ”keratoconus” OR words or phrase ”eye” OR words or phrase ”lens” Words or phrase ”aphakia” OR words or phrase ”cataract$” OR words or phrase ”ocular” OR words or phrase ”intraocular” OR words or phrase ”glaucoma” AND periodical title ”optical” words or phrase ”optic” OR words or phrase ”refractive” OR words or phrase ”astigmatism” OR words or phrase ”hyperopia” words or phrase ”hypermetropia” OR words or phrase ”myopia” OR words or phrase ”retinitis” OR words or phrase ”retina$” OR words or phrase ”retinopathy” words or phrase ”macular” OR words or phrase ”chorioretinitis” OR words or phrase ”choroid” OR words or phrase ”uveitis” OR words or phrase ”amblyopia”

Unique relevant records downloaded 3 0 0 0 0 0 0

10

Text 2.3. Results & Discussion (distance visual acuity data sources) 3878 records were identified by the June 2014 update searches. After deduplication, 1903 records were available for assessment. These results were provided as an Endnote library.

Numbers of records retrieved by June 2014 update searches and remaining after deduplication Database Records downloaded Records remaining after deduplication MEDLINE 1336 782 Embase 2539 1118 WHOLIS 3 3 Totals 3878 1903 All searches are compromises. Strategies trade off sensitivity against precision, and decisions are made by research teams about the numbers of records that they are able to process in the time available. The strategy developed is reasonably sensitive and precise. It could have been made more sensitive, for example by increasing the value of the adj operator (so that words could occur further apart but still be retrieved), by using AND rather than adj or by using ep as a floating subheading that is not linked to specific MeSH. Sensitivity might also have been increased by identifying more synonyms and spelling variants for the eye diseases which may result in blindness. These approaches would have generated many more studies to assess for relevance, but might have retrieved additional relevant studies.

The strategy could also have been made more precise perhaps by omitting some of the combinations of eye diseases and epidemiology terms as text words in the title and abstract. However, increasing search precision usually risks losing relevant studies.

Text 2.4. Systematic review of studies of presbyopia prevalence A systematic review of studies of presbyopia prevalence was conducted on October 9, 2015, with a search of the PubMed literature database (National Library of Medicine) for relevant evidence from October 1, 2007 onwards (adding directly to the search published by Holden et al, 2008 6 ), using the medical subject heading (MeSH) search terms “prevalence” AND (“presbyopia” OR “near vision impairment” OR “near visual impairment” OR “refractive error”). The search yielded 1697 unique papers, whose titles and abstracts were reviewed for relevance and design. Only population-based surveys with one or more measurements of near vision and/or the prevalence of spectacle wear for presbyopia were included. We only included data from studies greater than 500 participants. For data prior to our search period (October 1, 2007), we included sources used by Holden et al.* for prevalence estimates in regions where there were not more recent data. On full text review, papers were additionally excluded if they did not specify the number of eligible participants or participation rate, if data were from a specific population that could not be generalized to the population as a whole or there was an unspecified method for determining whether near vision impairment was the result of ocular disease or from refractive error.

Text 3. Methods for comparability of vision impairment definition Following the strategy of Stevens and colleagues 9 , we used logistic regression based on all of the data to convert from the four extended vision loss categories X to our two core levels Y where each regression had the following form: logit(PY ) = β · logit(PX ) + α The converted data (blind and MSVI) are then used in the models to predict the prevalence of vision impairment by country, age, sex, and year. Fit plots and regression coefficients in the Webappendix of Stevens and colleagues 9 .

Text 4. Methods for comparability of data aggregated by age In order to standardize age-range reporting across studies, we found a universal age pattern and then applied it to the wide age-range data, which allowed us to split the wide age-range data into five-year age groups. Following the strategy in Stevens and colleagues 9 , we did this by fitting a logistic regression as follows, using an age spline and study-specific random effects a as follows, with ph equal to the prevalence of vision impairment underlying age-specific observation h: yh ph

∼ Binom(nh , ph )

= logit−1 ast + X β . h i[h]

The β covariates represent a linear spline for age with knots at 40 and 70 years old. Then, for each wide age-range datapoint we created appropriate sets of 5-year age-ranges. With each corresponding set of 5-year age-range data we performed a grid-search to find an appropriate study-offet that allowed the population weighted 5-year age-range data estimate to be the same as its corresponding wide age-range datapoint. Once this had been performed for all wide age-range datapoints, the 5-year age-range estimates were substituted for their wide age-range counterparts.

11

Text 5. Methods for calculating prevalence of vision impairment by country, year, age, and sex We fit two hierarchical logistic regressions with mixed effects using the R package RStanArm to separately estimate the prevalence of blindness and MSVI in each country-age group. For observation o indexed by h, we define yh to be the number of subjects with vision impairment out of a total sample size nh . Our model includes a 5-level hierarchy, denoted a: • 270 (blind model) or 245 (MSVI model) studies are denoted st and indexed by i (a single published study may correspond to multiple studies if it covers different countries or years).

• 187 countries are denoted c and indexed by j.

• 21 subregions are denoted sb and indexed by k.

• 7 regions are denoted r and indexed by l.

• Global-level effects are denoted g.

Our regression is as follows, with ph equal to the prevalence of vision impairment underlying observation h: yh

∼

ph

=

Binom(nh , ph )

c st r r logit−1 ag + arl[h] + asb + a + a + b sex + c year + X β . h h i[h] k[h] j[h] i[h] l[h] l[h]

Where brl[h] and crl[h] are region-specific sex and linear year random slopes, respectively.

The variance of the study-specific random effects depends on whether the study is national or subnational, so: nat’l σ if study i is nationally representative σst,i = σ subnat’l otherwise.

Covariates represent characteristics of the data at the observation, study, and country levels. The observationspecific characteristics are age category, denoted by a three-piece linear spline z 0+ , z 1+ , z 2+ (with spline knots at age 40 and age 70), and an indicator variable for when presenting (vs. best-corrected) vision was measured (pres). A separate presenting offset was included for South Asia (presSA). Study-level covariates are an offset for a study that is rural-only, and an offset for studies that are urban-only.

The country-level covariates are mean years of education and a measure of health access. The mean number years of education covariate is an estimate broken down for each country by age and sex, based on censuses and nationally representative surveys from 175 countries 3;5 . The measure of health access is a country-level composite estimate constructed from nationally representative surveys 7 . Both education and health access were previously used as covariates for modelling the global prevalence of vision loss 9 .

All together, the covariates are: Xh β = β0 zh0+ + β1 zh1+ + β2 zh2+ + β3 presSAh + β4 presh + β5 rurali[h] + β6 urbani[h] + β7 health accessj[h] + β8 educj[h] Our model was fit using Markov Chain Monte Carlo, specifically Hamiltonian Monte Carlo as implemented by RStanArm 4 which relies on Stan 2 . We sampled 4 chains in parallel, with 500 warmup iterations and 1000 iterations total. The chains mixed well as indicated by the the Gelman-Rubin statistics which were close to 1.00 in all cases; traceplots are shown in Figure 1.

We present uncertainty intervals in summary estimates as the 10-90 percentiles of the distribution of draws, and percent the central estimate as the mean. We also calculate trends in vision impairment and its uncertainty by creating (for each draw) age-standardized total vision impairment estimates for all-ages and for ages 50 years and greater, for every five years from 1990 to 2020 and for all countries, regions, and the world.

To predict the prevalence of the extended categories severe, moderate, and mild vision impairment we used the predicted prevalences of blindness and MSVI, reversing the procedure described in section 4. Using all survey data which reported multiple definitions of vision impairment described in section 4, we fit logistic regressions to predict the proportion of MSVI made up by severe vision impairment, and the proportion of mild and no vision impairment made up by mild vision impairment. We fit the following regressions:

Prev(severe) logit = β0 + β1 logit(Prev(MSVI)) + β2 logit(Prev(blind)) Prev(MSVI)

Prev(mild) logit = β0 + β1 logit(Prev(MSVI)) + β2 logit(Prev(blind)) 1 − Prev(blind) − Prev(MSVI) For each draw from our set of blindness and MSVI samples, we predict the prevalence of severe, moderate, and mild vision impairment using these fitted logistic regression models. In a few cases among age groups >80 years, our estimates of the prevalence of blindness and MSVI sum to more than 100%. For each draw we normalize blind and MSVI estimates to sum to 100%.

12

Text 6. Methods for forecasting prevalence beyond 2015 After fitting our model, it is possible to derive any posterior estimate given the corresponding covariates, so forecasts for 2020 and beyond are derived in the same way as a prediction for 2015, by sampling from the posterior distribution of ph . Our model relies on two country-level covariates discussed in Text 5, health access and education, which it is impossible to predict decades into the future. These covariates are themselves based on a modeling exercise with very simple functional forms, so we felt comfortable extrapolating these forward to 2020. Beyond 2020, we simply held these values constant, with the goal of characterizing a possible future scenario, rather than providing a fully probabilistic forecast.

To forecast education to 2020, we used separate linear regressions for each country-age-sex group, regressing the number of years of education on year and year squared, achieving very close model fits in sample (average R2 = 0.9996).

For each country-age-sex we used our fitted model to make forecasts to 2020, and then held these constant from 2020 until 2050.

For the health access covariate, in order to forecast to 2020, we fit a linear model with an error term given by a Gaussian process with squared exponential covariance function, which served to smooth the forecasts in a nonparametric way, taking the correlation structure in time into account: yh ∼ N (aj[h] + bcj[h] yeari[h] , σ 2 ) + GP(0, k(·, ·))

(1)

where yh is the health access covariate in yeari[h] in country j[h], σ 2 is an error term, aj[h] are country level offsets and bcj[h] are country-level slopes. The covariance is over years, ignoring country, and it is parameterized as a squared exponential, where the lengthscale and signal variance parameters 8 are themselves parameters in the model, with N (0, 1) priors. After fitting this model in Stan (running 4 chains in parallel for 400 iterations each) to all of the data jointly, we made forecasts by calculating the posterior mean of health access covariate for every country to 2020, and then held these constant from 2020 until 2050.

With these forecasted covariates, we made predictions of crude prevalence for country-years 2020, 2030, 2040, and 2050. We then combined these with the United Nations Population Divisions (UNPOP) forecasts to 2050 to derive crude numbers affected and age-standardized prevalence.

13

References [1] Bourne R, Price H, Taylor H. New Systematic Review Methodology for Visual Impairment and Blindness for the 2010 Global Burden of Disease Study. Ophthalmic Epidemiology, 20(1):33–39, 2013.

[2] Carpenter B, Gelman A, Hoffman M, Lee D, Goodrich B, Betancourt M, Brubaker MA, Guo J, Li P, Riddell A. Stan: A probabilistic programming language. J Stat Softw, 2016.

[3] for Health Metrics Institute, (IHME) Evaluation. Global educational attainment 1970-2015, 2015.

[4] Gabry J, Goodrich B. rstanarm: Bayesian applied regression modeling via stan. R package version, 2:0–3, 2016.

[5] Gakidou Emmanuela, Cowling Krycia, Lozano Rafael, Murray Christopher JL. Increased educational attainment and its effect on child mortality in 175 countries between 1970 and 2009: a systematic analysis. The Lancet, 376 (9745):959–974, 2010.

[6] Holden Brien A, Fricke Timothy R, Ho S May, Wong Reg, Schlenther Gerhard, Cronj´e Sonja, Burnett Anthea, Papas Eric, Naidoo Kovin S, Frick Kevin D. Global vision impairment due to uncorrected presbyopia. Archives of ophthalmology, 126(12):1731–1739, 2008.

[7] Myerson R, Rosenfeld L, Lim S, Murray CLJ. Safe pregnancy and delivery: A systematic analysis of trends in the coverage of antenatal and intra-partum care. Lancet, pages 60169–4, 2011.

[8] Rasmussen CE, Williams CKI. Gaussian processes for machine learning, 2006.

[9] Stevens GA, White RA, Flaxman SR, Price H, Jonas JB, Keeffe J, Leasher J, Naidoo K, Pesudovs K, Resnikoff S, Taylor H, Bourne RRA. Global prevalence of vision impairment and blindness: magnitude and temporal trends, 1990–2010. Ophthalmology, 120(12):2377–2384, 2013.

14

Table 1. Countries and territories in analysis regions.

Subregion

Countries Central Europe, Eastern Europe, and Central Asia Asia, Central Armenia, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Mongolia, Tajikistan, Turkmenistan, Uzbekistan Europe, Central Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic, Hungary, Montenegro, Poland, Romania, Serbia, Slovakia, Slovenia, TFYR Macedonia Europe, Eastern Belarus, Estonia, Latvia, Lithuania, Moldova, Russian Federation, Ukraine High-income Asia Pacific, High Income Brunei Darussalam, Japan, Republic of Korea, Singapore Australasia Australia, New Zealand Europe, Western Andorra, Austria, Belgium, Cyprus, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Israel, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, United Kingdom Latin America, Southern Argentina, Chile, Uruguay North America, High Income Canada, United States of America Latin America and Caribbean Caribbean Antigua and Barbuda, Bahamas, Barbados, Belize, Cuba, Dominica, Dominican Republic, Grenada, Guyana, Haiti, Jamaica, Puerto Rico, Saint Lucia, Saint Vincent and the Grenadines, Suriname, Trinidad and Tobago Latin America, Andean Bolivia, Ecuador, Peru Latin America, Central Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Venezuela (Bolivarian Republic of) Latin America, Tropical Brazil, Paraguay North Africa and Middle East North Africa/Middle East Afghanistan, Algeria, Bahrain, Egypt, Iran (Islamic Republic of), Iraq, Jordan, Kuwait, Lebanon, Libyan Arab Jamahiriya, Morocco, Occupied Palestinian Territory, Oman, Qatar, Saudi Arabia, Sudan, Syrian Arab Republic, Tunisia, Turkey, United Arab Emirates, Yemen South Asia Asia, South Bangladesh, Bhutan, India, Nepal, Pakistan Southeast Asia, East Asia, and Oceania Asia, East China, Dem. People’s Republic of Korea, Taiwan Asia, Southeast Cambodia, Indonesia, Lao People’s Democratic Republic, Malaysia, Maldives, Mauritius, Myanmar, Philippines, Seychelles, Sri Lanka, Thailand, Timor-Leste, Viet Nam Oceania Fiji, Kiribati, Marshall Islands, Micronesia (Fed. States of), Papua New Guinea, Samoa, Solomon Islands, Tonga, Vanuatu Sub-Saharan Africa Sub-Saharan Africa, Central Angola, Central African Republic, Congo, Democratic Republic of the Congo, Equatorial Guinea, Gabon Sub-Saharan Africa, East Burundi, Comoros, Djibouti, Eritrea, Ethiopia, Kenya, Madagascar, Malawi, Mozambique, Rwanda, Somalia, Uganda, United Republic of Tanzania, Zambia Sub-Saharan Africa, Southern Botswana, Lesotho, Namibia, South Africa, Swaziland, Zimbabwe Sub-Saharan Africa, West Benin, Burkina Faso, Cˆote d’Ivoire, Cameroon, Cape Verde, Chad, Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Mali, Mauritania, Niger, Nigeria, S˜ao Tom´e and Pr´ıncipe, Senegal, Sierra Leone, Togo

15

Table 2. Characteristics of data sources used in the analysis. New sources since the original systematic review are marked with an asterisk in the column marked ‘Country’ Country

Coverage

16

Age range

Total examined

Urban rural

local local

Year (NS = not specified) 2010 2005

Afghanistan* Argentina

/

Rapid

Presenting or bestcorrected Both Both

Core visual acuity level

Reference

50-99 50-99

1862 4302

both urban

Yes Yes

blind, low vision blind, low vision

No

Bestcorrected

blind, low vision

urban urban

No No

Both Both

blind, low vision blind, low vision

2614

urban

No

Both

low vision

5-8

1738

urban

No

Both

blind

12

2353

urban

No

Both

blind, low vision

subnational 2007-2009

4-6

1188

urban

No

Presenting

low vision

Bangladesh Bangladesh

national local

1999-2000 2005

30-99 50-99

11624 4868

both rural

No Yes

Both Presenting

blind, low vision blind, low vision

Barbados

national

1988-1992

40-99

4068

both

No

blind, low vision

Benin

national

1990

0-99

7047

both

No

Bhutan*

national

2009

50-99

4046

both

Yes

Botswana

national

1998

60-99

372

both

No

Bestcorrected Bestcorrected Bestcorrected Presenting

blind

Brazil

local

2002

0-99

801

urban

No

Both

blind, low vision

Brazil

local

2003

50-99

2224

urban

Yes

Both

blind, low vision

rapid repository Nano, M. E., H. D. Nano, et al. (2006). Rapid assessment of visual impairment due to cataract and cataract surgical services in urban Argentina. Ophthalmic Epidemiology 13(3): 191-197.

Casson R, Giles L, Newland HS. Prevalence of blindness and visual impairment in an elderly urban population. Aust N Z J Ophthalmol. 1996 Aug;24(3):23943.

BLUE Mountains Sydney Microdata Weih LM, VanNewkirk MR, McCarty CA, Taylor HR. Age-specific causes of bilateral visual impairment. Archives of Ophthalmology 2000; 118(2): 264-9.

Foran S, Rose K, Wang JJ, Mitchell P. Correctable visual impairment in an older population: The Blue Mountains Eye Study. American Journal of Ophthalmology 2002; 134(5): 712-9.

Robaei D, Rose K, Ojaimi E, et al. Visual acuity and the causes of visual loss in a population-based sample of 6-year-old Australian children. 2005 JOphthalmology; 112(7): 1275-82 Robaei D, Huynh SC, Kifley A, Mitchell P. Correctable and Non-Correctable Visual Impairment in a Population-Based Sample of 12-Year-Old Australian Children. 2006; 142(1): 112-8.e1.

Pai AS, Wang JJ, Samarawickrama C, Burlutsky G, Rose KA, Varma R, Wong TY, Mitchell P. Prevalence and risk factors for visual impairment in preschool children the sydney paediatric eye disease study. Ophthalmology.

2011 Aug;118(8):1495-500.

Bourne Bangladesh National Eye Survey Microdata (1999) Wadud, Z., H. Kuper, et al. (2006). Rapid assessment of avoidable blindness and needs assessment of cataract surgical services in Satkhira District, Bangladesh. British Journal of Ophthalmology 90(10): 1225-9.

Hyman, L., S. Y. Wu, et al. (2001). Prevalence and causes of visual impairment in The Barbados Eye Study.[see comment]. Ophthalmology 108(10): 1751-6 Negrel AD, Avognon Z, Minassian DC, Babagbeto M, Oussa G, Bassabi S.: Blindness in Benin. 1995. Med Trop (Mars) 55 (4 Pt 2) 409-414.

Lepcha NT, Chettri CK et al., (2013) Rapid Assessment of Avoidable Blindness in Bhutan, Ophthalmic Epidemiology. 20;4:212-234 Clausen T, Romoren TI, Ferriera M, Kristensen P, Ingstad B, HolmboeOttensen G. Chronic diseases and health inequalities in older persons in Botswana (southern Africa): A national survey. 2005. The Journal of Nutrition, Health and Aging. 9 (6 Araujo Filho, A., S. R. Salomao, et al. (2008). Prevalence of visual impairment, blindness, ocular disorders and cataract surgery outcomes in low-income elderly from a metropolitan region of Sao Paulo–Brazil. Arquivos Brasileiros de Oftalmolog Arieta, C. E. L., D. F. de Oliveira, et al. (2009). Cataract remains an important cause of blindness in Campinas, Brazil. Ophthalmic Epidemiology 16(1): 58-63.

Australia

local

1992

70-99

1446

urban

Australia Australia

local local

1992-1994 1992-1996

49-99 40-99

3650 4386

Australia

local

1997-1999

50-99

Australia

local

2003-2005

Australia

local

2004-2005

Australia

blind blind, low vision

Country

Coverage

Age range

Total examined

Urban rural

local

Year (NS = not specified) 2004

Brazil

0-99

3678

urban

Brazil

local

NS

0-99

2485

Bulgaria

local

1993

50-99

Burundi*

local

2010

Cambodia

17

Core visual acuity level

Reference

No

Presenting or bestcorrected Both

blind, low vision

urban

No

Both

blind, low vision

6173

both

No

Presenting

blind, low vision

50-99

3665

rural

Yes

Both

blind, low vision

subnational 1996

0-99

5803

both

No

Presenting

blind, low vision

Cambodia

subnational 2002

50-99

both

Yes

Presenting

blind, low vision

Cambodia

national

50-99

both

Yes

Presenting

blind, low vision

Cameroon

subnational 1992

6-99

10647

both

No

Presenting

blind, low vision

Cameroon

local

NS

40-99

1787

rural

Yes

Presenting

blind, low vision

Cameroon

local

NS

40-99

2215

urban

Yes

Presenting

blind, low vision

Cape Verde

subnational 1998

0-99

3374

both

No

Presenting

blind, low vision

Chile

local

1998

5-15

5284

urban

No

Both

blind, low vision

Chile

local

2006-2007

50-99

2915

both

Yes

Both

blind, low vision

China

national

1987

0-99

1579316

both

No

blind, low vision

China

local

1996

50-99

5052

rural

No

Bestcorrected Presenting

China

local

1997

50-99

5342

rural

No

Both

blind, low vision

China

local

1998

5-15

5882

urban

No

Both

blind, low vision

China

subnational 1999-2000

0-99

12644

rural

No

Presenting

blind

Salomao, S. R., R. W. Cinoto, et al. (2008). Prevalence and causes of vision impairment and blindness in older adults in Brazil: the sao paulo eye study.

Ophthalmic Epidemiology 15(3): 167-75.

Schellini SA, Durkin SR, Hoyama E, Hirai F, Cordeiro R, Casson RJ, Selva D, Padovani CR. Prevalence and causes of visual impairment in a Brazilian population: the Botucatu Eye Study. BMC Ophthalmol. 2009 Aug 19;9:8.

Vassileva, P., S. C. Gieser, et al. (1996). Blindness and visual impairment in western Bulgaria. Ophthalmic Epidemiology 3, 143-9.

Kandeke L, Mathenge W, Giramahoro C, et al. 2012. Rapid Assessment of Avoidable Blindness in two Northern Provinces of Burundi without Eye Services. Ophthalmic Epidemiology 19(4): 211-215.

Rutzen, A. R., N. J. Ellish, et al. (2007). Blindness and eye disease in Cambodia. Ophthalmic Epidemiology 14(6): 360-6.

Sub-Committee for the Prevention of Blindness, Cambodia. Results of rapid assessment of cataract surgical services. Cambodia: Battabang. 2002.

Cambodia 2007 - contact: Dr. Do Seiha RAAB unpublished report without authors Wilson, M. R., M. Mansour, et al. (1996). Prevalence and causes of low vision and blindness in the Extreme North Province of Cameroon, West Africa.

Ophthalmic Epidemiology 3(1): 23-33.

Oye JE, Kuper H, Dineen B, Befidi-Mengue R, Foster A.: Prevalence ad causes of blindess and visual imapirment in Muyuka: a rural health distric in South West Province, Cameroon. 2006. British Journal of Ophthalmology. 90 (5) 538-542.

Oye JE, Kuper H.: Prevalence and causes of blindness and visual impairment in Limbe urban area, South West Province, Cameroon. 2007. British Journal of Ophthalmology. 91 1435-1439.

Schemann JF, Inocencio F, Monteiro ML, Andrade J, Auzemery A, Guelfi Y. :Blindness and Low Vision in cape Verde Islands: Results of a National Eye Survey. 2006. Ophthalmic Epidemiology. 13(4), 219-226.

Gilbert CE et al. Prevalence and causes of functional low vision in school-age children: Results from standardized population surverys in Asia, Africa, and Latin America Investigative Ophthalmology & Visual Science, March 2008, Vol. 49, No. 3 Fernando Barr , Arcg, Chil. Oftal 2007 Anlisis de las barreras,cobertura y resultados postoperatorios de ciruga de catarata determinados mediante encuesta rpida de ceguera evitable en la VIII regin, Chile Zhang, et al.national epidemiological survey of blindness and low vision in ChinaChinese medical journal 1992;7:603-608 Zhao J et al. prevalence of blindness and cataract surgery in Shunyi Country, ChinaAJO 1998 S Li, J Xu, M He, et al.A Survey of Blindness and Cataract Surgery in Doumen County, China. Ophthalmology 1999;106:16021609 Gilbert CE et al. Prevalence and causes of functional low vision in school-age children: Results from standardized population surverys in Asia, Africa, and Latin America Investigative Ophthalmology & Visual Science, March 2008, Vol. 49, No. 3 S Dunzhu, FS Wang, P Courtright et al. (2003)Blindness and eye diseases in Tibet: findings from a randomised, population based survey Br J Ophthalmol 2003;87:14431454

2007

/

Rapid

blind, low vision

Country

Coverage

18

Age range

Total examined

Urban rural

China

Year (NS = not specified) subnational 2001

35-99

4438

urban

No

China

local

2002-2003

5-15

4359

urban

No

China

local

2003

60-99

3040

both

No

China

local

2004

3-6

28738

both

China

local

2005

12-18

2454

China

subnational 2006-2007

50-99

China

local

2006-2007

China

local

China

/

Rapid

Presenting or bestcorrected Bestcorrected Both

Core visual acuity level

Reference

blind, low vision

Bejing Eye Study microdata

blind, low vision

Gilbert CE et al. Prevalence and causes of functional low vision in school-age children: Results from standardized population surverys in Asia, Africa, and Latin America Investigative Ophthalmology & Visual Science, March 2008, Vol. 49, No. 3 Li L, Guan H, kun P, Zhou J, Gu H. Prevalence and causes of visual impairment among the elderly in Nantong, China. Eye, 2008; 22:1069-75.

Lu Q, Zheng Y, Sun B, Cui T, Congdon N, Hu A, Chen J, Shi J. A populationbased study of visual impairment among pre-school children in Beijing: the Beijing study of visual impairment in children. Am J Ophthalmol. 2009 Jun;147(6):1075-81 He, M., W. Huang, et al. (2007). Refractive Error and Visual Impairment in School Children in Rural Southern China. Ophthalmology 114(2): 374-382.

Zhao, J., L. B. Ellwein, et al. (2010). Prevalence of Vision Impairment in Older Adults in Rural China:: The China Nine-Province Survey. Ophthalmology 117(3): 409-416.

Liang YB, Friedman DS, Wong TY, et al.(2008). Prevalence and Causes of Low Vision and Blindness in a Rural Chinese Adult Population The Handan Eye Study. Ophthalmology 115(11):1965-72.

Li Z, Cui H, Liu P, Zhang L, Yang H, Zhang L. Prevalence and causes of blindness and visual impairment among the elderly in rural southern Harbin, China. Ophthalmic Epidemiol, 2008; 15:334-8.

Xiao B, Kuper H, Guan C, Bailey K, Limburg H. Rapid assessment of avoidable blindness in three counties, Jiangxi Province, China. Br J Ophthalmol 2010;94 1437-1442 Song W, Sun X, Shao Z, Zhou X, Kang Y, Sui H, Yuan H. 2010. Prevalence and causes of visual impairment in a rural North-east China adult population: a population-based survey in Bin County, Harbin. Acta Ophthalmol. 2010 Sep;88(6):669-84 Xiao B, Kuper H, Guan C, Bailey K, Limburg H. Rapid assessment of avoidable blindness in three counties, Jiangxi Province, China. Br J Ophthalmol 2010;94 1437-1507 Xiao B, Kuper H, Guan C, Bailey K, Limburg H. Rapid assessment of avoidable blindness in three counties, Jiangxi Province, China. Br J Ophthalmol 2010;94 1437-1450 N Congdon, Y Wang, Y Song, et al. (2008)Visual Disability, Visual Function, and Myopia among Rural Chinese Secondary School Children: The Xichang Pediatric Refractive Error Study (X-PRES)Report 1.Invest Ophthalmol Vis Sci. 2008;49:28882894 Min Wu, RAAB in Luliang County, China (2008) unpublished Xiao B, Fan J, Deng Y, Ding Y, Muhit M, Kuper H.Using key informant method to assess the prevalence and causes of childhood blindness in Xiuâ&#x20AC;&#x2122;shui County, Jiangxi Province, Southeast China. Ophthalmic Epidemiol. 2011 Feb;18(1):30-5.

CHINA INNER MONGOLIA SHANGDU RAPID DATA CHINA INNER MONGOLIA TUOKETUO RAPID DATA CHINA SICHUAN DECHANG RAPID DATA CHINA SICHUAN MIANNING RAPID DATA

blind, low vision

No

Bestcorrected Presenting

rural

No

Both

blind

45747

rural

No

Both

blind, low vision

30-97

6830

rural

No

Both

blind, low vision

2006-2007

50-96

5057

rural

No

Presenting

blind, low vision

local

2007

50-99

urban

Yes

Both

blind, low vision

China

local

2007

40-99

4956

rural

No

Both

blind

China

local

2007

50-99

3840

urban

Yes

Both

blind, low vision

China

local

2007

50-99

2861

urban

Yes

Both

blind, low vision

China

subnational 2007

11-17

1892

rural

No

Both

blind

China China

subnational 2008 local 2009

50-99 0-15

2842 23675

both both

Yes No

Both Presenting

blind, low vision blind

China China China China

local local local local

50-99 50-99 50-99 50-99

1076 939 1723 2865

both both both both

Yes Yes Yes Yes

Both Both Both Both

blind, blind, blind, blind,

2010 2010 2011 2011

blind, low vision

low low low low

vision vision vision vision

Country

Coverage

Age range

Total examined

Urban rural

China*

Year (NS = not specified) subnational 2006

0-99

125641

both

Yes

China*

subnational 2006

0-99

125641

both

No

Bestcorrected

blind, low vision

China*

subnational 2006

50-99

5662

urban

No

Both

blind, low vision

China*

local

2008

60-99

1305

urban

No

Both

blind, low vision

China*

local

2008-2009

1-99

10384

rural

No

Bestcorrected

blind, low vision

China*

subnational 2008-2009

5-18

1675

rural

No

Both

blind

China*

local

2009

60-99

4545

urban

No

Both

blind, low vision

China*

local

2009

50-99

924

urban

No

Both

blind, low vision

China*

subnational 2009-2010

50-99

6482

rural

Yes

Presenting

blind, low vision

China*

subnational 2010

50-99

6150

both

No

Presenting

blind, low vision

China*

subnational 2010

7-99

20072

rural

No

Both

blind, low vision

China*

local

2010

40-99

4104

both

No

Bestcorrected

blind, low vision

China* China*

local local

2012 NS

50-99 0-99

2008 2801

both urban

Yes No

Both Presenting

blind, low vision blind, low vision

China*

subnational NS

50-99

2133

rural

No

Both

blind, low vision

China*

local

NS

5-13

663

both

No

Both

blind

China, Hong Kong SAR Congo

local

1998

60-99

3441

urban

No

Both

blind, low vision

national

1988

0-99

6185

both

No

Bestcorrected

blind, low vision

/

Rapid

Presenting or bestcorrected Bestcorrected

Reference

blind, low vision

Wei M, Chen H, Fan Y, Pathai S. Prevalence and causes of visual impairment and blindness in Sichuan province of China. Int J Ophthalmol 2010: 3(1); 83-89.

Wei M, Chen H, Fan Y, Pathai S. Prevalence and causes of visual impairment and blindness in Sichuan province of China. Int J Ophthalmol 2010: 3(1); 83-89.

Lu H, Guan H, Dai Z, et al. Prevalence of blindness and moderate and severe visual impairment among adults aged 50 years or above in Qigong City of Jiangsu Province: the China nine-orovince survey. Chin J Ophthalmology 2012; 48 (3): 205-210.

Zhou J, Yuan Y, Zhang X, Guan HJ. A prevalence investigation of blindness and low vision in 2008 among adults aged 60 years or above in 2 villages of Nantong. Zhonghua Yan Ke Za Zhi. 2012 Oct;48(10):908-14.

Zhang Y, Wang H, Liu J, et al. Prevalence of blindness and low vision: a study in the rural Heilongjiang Province of China. Clinical and experimental ophthalmology 2012; 40: 484-489.

Li Z, Xu Ke et al., (2014) Population-based survey of refractive error among school-aged children in rural northern China: the Heilongjiang eye study. Clinical and Experimental Ophthalmology 2014; 42: 379385 Zhu M, Tong X, Zhao R, et al. Visual impairment and spectacle coverage rate in Baoshan district, China: population-based study. BMC Public Health 2013; 13: 311-324.

Wang L, Huang W, He M. Causes and five year incidence of blindness and visual impairment in urban southern China: the Liwan eye study. IOVS 2013; 54 (6): 4117-4121.

Li EY, Liu Y et al., (2013) Prevalence of Blindness and Outcomes of Cataract Surgery in Hainan Province in South China. Ophthalmology. 120:2176-2193 Yao Y, Shao J, Sun W, Zhu J, Hong Fu D, Guan H, Liu Q. Prevalence of blindness and causes of visual impairment among adults aged 50 years or above in southern. Jiangsu Province of China. Pak J Med Sci. 2013 Sep;29(5):1203-7.

Li X, Zhou Q, Sun L, et al. Prevalence of blindness and low vision in a rural population in Northern China: Preliminary results from a population-based survey. Ophthalmic Epidemiology 2012,19(5); 272277.

Mai Dina NB, Xie TY, Chen XY, Mi Nawaer AB, Fu J. Survey of blindness and low vision among residents in Shuimogou District, Urumqi, China in 2010.

Zhonghua Yi Xue Za Zhi. 2012 Mar 20;92(11):743-7. rapid repository Li J, Zou K, Bi W. Status survey of blindness and low vision of population in Kongtong district of Pinging city, Gansu Province. Int J Ophthalmic 2011; 11 (8): 1452-1454.

Li J, Zhong H, Cai N, et al. The prevalence and causes of visual impairment in an elderly Chinese Bai ethnic rural population . The Yunnan Minority Eye Study. IOVS 2012; 53 (8): 4498-4508.

Guo Y, Liu LJ et al., (2014) Visual impairment and spectacle use in schoolchildren in rural and urban regions in Beijing. Eur J Ophthalmol; 24 (2): 258-265 Michon, Lau, Chan, Ellwein.prevalence of visual impairment,blindness, and cataract surgery in the Hong Kong elderly BJO 2002;86:133-142 Annon Weekly Epidemiological Record, 1990:65:249-256 (N33)

19

Core visual acuity level

Country

Coverage

Age range

Total examined

Urban rural

local

Year (NS = not specified) 2005

Cuba

50-99

2716

urban

Denmark

local

1986-1988

60-80

946

Dominican Republic Ecuador

national

2008

50-99

national

2009

Egypt

20

Core visual acuity level

Reference

Yes

Presenting or bestcorrected Both

blind, low vision

urban

No

Both

blind, low vision

3873

both

Yes

Both

blind, low vision

Juan R. Hernndez Silva, Marcelino Ro Torres y Carmen Ma. Padilla Gonzlez Resultados del RACSS en Ciudad de La Habana, Cuba, 2005 Rev Cubana Oftalmol 2006;19(1) Buch, H., T. Vinding, et al. (2001). Prevalence and causes of visual impairment according to World Health Organization and United States criteria in an aged, urban Scandinavian population: the Copenhagen City Eye Study.

Ophthalmology 108(12): 2 Diaz, Evelyn Garcia (2008) RAAB Dominican Republic, Unpublished

50-99

4012

both

Yes

Both

blind, low vision

subnational 1994

7-15

5839

urban

No

Bestcorrected

low vision

Egypt Egypt Egypt Egypt Egypt Egypt*

local local local local local subnational

2009 2009 2010 2010 2010 2007-2008

50-99 50-99 50-99 50-99 50-99 40-99

2918 2905 2706 2811 2953 525

rural rural rural rural rural urban

Yes Yes Yes Yes Yes No

Both Both Both Both Both Presenting

blind, blind, blind, blind, blind, blind,

El Salvador Eritrea Estonia

national national local

2011 2008 NS

50-99 50-99 65-99

3399 3163 910

both both urban

Yes Yes No

Both Both Bestcorrected

blind, low vision blind, low vision blind, low vision

Ethiopia

local

1994-1995

0-99

7423

both

No

Presenting

blind, low vision

Ethiopia

national

2005-2006

0-99

both

No

Presenting

blind, low vision

Ethiopia

subnational 2009

0-16

58480

both

No

Presenting

blind

Ethiopia

subnational NS

7-99

11441

both

No

Presenting

blind, low vision

Ethiopia

local

NS

40-99

2639

rural

No

Presenting

blind, low vision

Ethiopia*

local

2010-2011

7-18

4238

rural

No

Both

blind

Fiji

national

2006-2007

0-15

both

No

low vision

Fiji

subnational 2009

both

No

Bestcorrected Presenting

40-99

1381

/

Rapid

low low low low low low

vision vision vision vision vision vision

blind, low vision

Limburg H, Silva JC, Foster A. Cataract in Latin America: findings from nine recent surveys. Rev Panam Salud Publica. 2009;25(5):44955.

El-Bayoumy, B. M., A. Saad, et al. (2007). Prevalence of refractive error and low vision among schoolchildren in Cairo. Eastern Mediterranean Health Journal 13(3): 575-9.

EGYPT KAFARELSHEAKHSHABAS RAPID ASSESSMENT EGYPT FAYOUM KASR BASEAL RAPID ASSESSMENT EGYPT MENYA QALTA RAPID ASSESSMENT EGYPT BANISWEILF MAZORA RAPID ASSESSMENT EGYPT SOHAG BAGA RAPID ASSESSMENT Mousa, A, Courtright P et al., (2014) Prevalence of Visual Impairment and Blindness in Upper Egypt: A Gender-based Perspective. Ophthalmic Epidemiology. 21(3): 190-196 EL SALVADOR RAPID DATA Andreas Mueller, RAAB in Eritrea (2008) unpublished Seland, Vingerling,Augood, Bentham, Chakravarthy et al. (2009) Visual Impairment and quality of life in the Older European Population, the EUREYE study Act Ophth 2009 Zerihun 1997 Blindness and low vision in Jimma zone, Ethiopia: results of a population based survey Ophthalmic Epidemiology p19-25 National survey on blindness, low vision and trachoma in Ethiopia.Federal MOH of Ethiopia, The Carter Center, CBM, ITI, ORBIS Int.Ethiopia and LfW, Opthalmol Society of Ethiopia, Ethiopian Public Health Association.

Addis Ababa, Ethiopia 2006.

Demissie BS, Solomon AW. Magnitude and causes of childhood blindness and severe visual impairment in Sekoru District, Southwest Ethiopia: a survey using the key informant method. Trans R Soc Trop Med Hyg. 2011 Sep;105(9):507-11.

Cerulli, L., C. Cedrone, et al. (1984). Assessment of visual status of the population in seven regions of Ethiopia. Revue Internationale du Trachome et de Pathologie Oculaire Tropicale et Subtropicale et de Sante Publique(2-4): 127-42.

Melese 2003 Low vision and blindness in adults in Gurage zone, Central Ethiopia Br J Ophth p677-680 Mehari Z, Yimer AW., (2013) Prevalence of Refractive Errors among school children in rural central Ethiopia. Clin Exp Optom; 96: 65-74 Cama AT, Sikivou BT, Keeffe JE. Childhood visual impairment in Fiji. Arch Ophthalmol. 2010 May;128(5):608-12.

Ramke J, Brian G, Maher L, Qalo Qoqonokana M, Szetu J. Prevalence and causes of blindness and low vision among adults in Fiji. Clin Experiment Ophthalmol. 2012 Jul;40(5):490-6

Country

Coverage

21

Age range

Total examined

Urban rural

national

Year (NS = not specified) 2000-2001

Finland

30-99

6663

both

No

France

local

NS

65-99

702

urban

No

Bestcorrected

blind, low vision

Gambia

national

1986

0-99

8174

both

No

Presenting

blind

Gambia

national

1996

5-99

13046

both

No

Presenting

blind, low vision

Gambia Ghana

subnational 2007 local 2001

50-99 40-99

2298

both both

Yes No

Presenting Both

blind, low vision blind, low vision

Ghana*

local

2006-2008

40-99

5603

urban

No

Both

blind, low vision

Greece

local

NS

65-99

586

urban

No

Bestcorrected

blind, low vision

Guatemala

subnational 2004

50-99

4806

both

Yes

Both

blind, low vision

Honduras*

national

2013

50-99

2999

both

Yes

Presenting

blind, low vision

Iceland

local

1996

50-99

1635

urban

No

Bestcorrected

blind, low vision

India

national

1986-1989

0-99

both

No

Presenting

blind

India

local

1993-1995

3-18

3669

urban

No

Both

blind, low vision

India

local

1995-1997

6-99

9012

rural

No

Both

blind

India

local

1996

0-99

10293

both

No

Presenting

blind, low vision

India

local

1999

50-99

4642

both

No

Both

blind, low vision

India

subnational 1999-2001

50-99

63337

both

No

Both

blind, low vision

India

local

50-99

5411

rural

No

Presenting

blind

2000

/

Rapid

Presenting or bestcorrected Presenting

Core visual acuity level

Reference

blind

Laitinen, A., S. Koskinen, et al. (2005). A nationwide population-based survey on visual acuity, near vision, and self-reported visual function in the adult population in Finland. Ophthalmology 112, 2227-2237.

Seland, Vingerling,Augood, Bentham, Chakravarthy et al. (2009) Visual Impairment and quality of life in the Older European Population, the EUREYE study Act Ophth 2009 Faal H, Minassian D, Sowa S, Foster A.: National survey of blindness and low vision in The Gambia. 1989. British Journal of Ophthalmology 73 82-87.

Faal H, Minassian DC, dolin PJ, Mohamed AA, Ajewole J, Johnson GJ.: Evaluation of a national eye care programme: re-survey after 10 years. 2000.

British Journal of Ophthalmology. 84 948-951.

Gambia 2007 Guzek JP, Anyomi FK, Fiadoyor S, Nyonator F.: Prevalence of blindness in people over 40 years in the Volta region of Ghana. 2005. Ghana Medical Journal. 39 (2) 55-62.

Budenz D, Bandi J, Barton K, et al (2012) Blindness and Visual impairment in an Urban West African Population: The Tema Eye Study. Ophthalmology 119 (9): 1744-1753.

Seland, Vingerling,Augood, Bentham, Chakravarthy et al. (2009) Visual Impairment and quality of life in the Older European Population, the EUREYE study Act Ophth 2009 Beltranena F, Casasola K, Silva JC, Limburg H. Cataract blindness in 4 regions in Guatemala:results of a population-based survey.Ophthalmology.

2007;114(8):155863.

Alvarado D, Rivera B, Lagos L, Ochoa M, Starkman I, Castillo M, et al. Encuesta nacional de ceguera y deficiencia visual evitables en Honduras. Rev Panam Salud Publica. 2014;36(5):3005.

Gunnlaugsdottir E, Arnarsson A, Jonasson F. Prevalence and causes of visual impairment and blindness in Icelanders aged 50 years and older: the Reykjavik Eye Study. Acta Ophthalmol. 2008 Nov;86(7):778-85.

Mohan, Survey of blindness in India 1986-1989, National Programme for control of blindness Ministry of Health of Govt of India Kalikivayi, V., T. J. Naduvilath, et al. (1997). Visual impairment in school children in southern India.[erratum appears in Indian J Ophthalmol 1997 Sep;45(3):168]. Indian Journal of Ophthalmology 45(2): 129-34.

Thulasiraj, R. D., P. K. Nirmalan, et al. (2003). Blindness and vision impairment in a rural South Indian population: The Aravind Comprehensive Eye Survey. Ophthalmology 110(8): 1491-1498.

Dandona, R., L. Dandona, et al. (2002). Moderate visual impairment in India: the Andhra Pradesh Eye Disease Study. British Journal of Ophthalmology 86(4): 373-7.

Thulasiraj, R. D., R. Rahamathulla, et al. (2002). The Sivaganga eye survey: I. Blindness and cataract surgery. Ophthalmic Epidemiology 9(5): 299-359 Murthy, G. V., S. K. Gupta, et al. (2005). Current estimates of blindness in India. British Journal of Ophthalmology 89(3): 257-60.

Nirmalan PK, Thulasiraj RD, Maneksha V, Rahmathullah R, Ramakrishnan R, Padmavathi A and others. 2002. A population based eye survey of older adults in Tirunelveli district of south India: blindness, cataract surgery, and visual outcomes. Briti

Country

Coverage

Age range

Total examined

Urban rural

local

Year (NS = not specified) 2000-2001

India

5-15

5062

both

India

local

2001-2003

40-99

3924

India

local

2002

0-15

India

local

2002

India

22

Core visual acuity level

Reference

No

Presenting or bestcorrected Both

blind, low vision

rural

No

Both

blind, low vision

10605

rural

No

Both

blind, low vision

50-99

1505

rural

No

Presenting

blind

subnational 2007

50-99

40447

both

Yes

Presenting

blind, low vision

India

local

2009

50-99

2004

both

Yes

Bestcorrected

blind, low vision

India India

local local

2011 NS

50-99 50-99

2907 4284

both rural

Yes No

Both Both

blind, low vision blind, low vision

India

local

NS

0-15

8684

rural

No

Bestcorrected

blind

India*

local

2006-2007

50-99

2160

rural

Yes

Presenting

blind, low vision

India*

local

2010

50-99

2747

both

Yes

Presenting

blind, low vision

India*

local

2011

50-99

2137

rural

Yes

Presenting

blind, low vision

India*

subnational 2011-2012

40-99

7378

both

Yes

Presenting

blind, low vision

India*

subnational NS

30-99

4706

rural

No

Both

blind, low vision

Indonesia

local

2001-2002

21-99

989

both

No

Presenting

blind, low vision

Indonesia

local

2004

50-99

both

Yes

Presenting

blind, low vision

Iran (Islamic Republic of)

local

2002

1-99

urban

No

Both

blind, low vision

Gilbert CE et al. Prevalence and causes of functional low vision in school-age children: Results from standardized population surverys in Asia, Africa, and Latin America Investigative Ophthalmology & Visual Science, March 2008, Vol. 49, No. 3 Vijaya, L., R. George, et al. (2006). Prevalence and causes of blindness in the rural population of the Chennai Glaucoma Study. British Journal of Ophthalmology 90(4): 407-10.

Nirmalan, P. K., P. Vijayalakshmi, et al. (2003). The Kariapatti pediatric eye evaluation project: Baseline ophthalmic data of children aged 15 years or younger in Southern India. American Journal of Ophthalmology 136(4): 703-709.

Chandrashekhar TS, Bhat HV, Pai RP, Nair SK.: Prevalence of blindness and its causes among those aged 50 years and above in rural Karnataka, South India. 2007. Tropical Doctor. 37, 18-21.

Neena, J., J. Rachel, et al. (2008). Rapid Assessment of Avoidable Blindness in India. PLoS ONE [Electronic Resource] 3(8): e2867.

Dhake PV, Dole K, Khandekar R, Deshpande M. Prevalence and causes of avoidable blindness and severe visual impairment in a tribal district of Maharashtra, India. Oman J Ophthalmol. 2011 Sep;4(3):129-34.

KOLAR KARNATAKA RAPID ASSESSMENT Murthy, G. V. S., L. B. Ellwein, et al. (2001). A population-based eye survey of older adults in a rural district of Rajasthan: I. Central vision impairment, blindness, and cataract surgery. Ophthalmology 108(4): 679-685.

Dorairaj SK, Bandrakalli P, Shetty C, Vathsala R, Misquith D, Ritch R.: Childhood blindness in a rural population of Southern India: Prevalence and etiology. 2008. Ophthalmic Epidemiology. 15(3), 176-182.

Khanna RC, Marmamula S, Krishnaiah S, Giridhar P, Chakrabarti S, Rao GN. Changing trends in the prevalence of blindness and visual impairment in a rural district of India: systematic observations over a decade. Indian J Ophthalmol.

2012 Sep-Oct Patil S, Gogate P1, Vora S, Ainapure S, Hingane RN, Kulkarni AN, Shammanna BR.Prevalence, causes of blindness, visual impairment and cataract surgical services in Sindhudurg district on the western coastal strip of India.

Indian J Ophthalmol. 2 Rapid assessment of Avoidable Blindness and willingness to pay for cataract surgery in tribal region of Surat district of Gujarat state, India.

Marmamula S, Narsaiah S et al., (2013) Visual Impairment in the South Indian State of Andhra Pradesh: Andhra Pradesh - Rapid Assessment of Visual Impairment (AP-RAVI) Project.

PLoS ONE 8(7): e70120. doi:10.1371/journal.pone.0070121 Nangia V, Jonas JB et al., (2013) Visual impairment and blindness in rural central India: the Central India Eye and Medical Study. Acta Ophthalmol.

2013: 91: 483488 Saw, S. M., R. Husain, et al. (2003). Causes of low vision and blindness in rural Indonesia. British Journal of Ophthalmology 87(9): 1075-8.

Indonesia 2004 - RACSS unpublished report, not sure of principal investigator, Lombok Fotouhi, A., H. Hashemi, et al. (2004). The prevalence and causes of visual impairment in Tehran: the Tehran Eye Study. British Journal of Ophthalmology 88(6): 740-5.

4565

/

Rapid

Country

Coverage

Age range

Total examined

Urban rural

local

Year (NS = not specified) 2005

Iran (Islamic Republic of)

7-15

5544

both

Iran (Islamic Republic of)

local

2008-2009

40-64

5190

Iran (Islamic Republic of)

local

2009

50-99

Iran (Islamic Republic of)

local

NS

Iran (Islamic Republic of)*

/

Rapid

Reference

blind

urban

No

Presenting

low vision

2819

both

Yes

Presenting

blind, low vision

0-15

136000

both

No

Presenting

blind

subnational 2006

0-87

6960

both

No

Bestcorrected

blind, low vision

Iran (Islamic Republic of)*

local

2009-2010

40-64

5188

urban

No

Both

low vision

Italy

local

1988

40-87

600

rural

No

Bestcorrected

blind, low vision

Italy

local

2000

40-99

843

rural

No

Both

blind, low vision

Italy

local

NS

65-99

601

urban

No

Bestcorrected

blind, low vision

Japan

local

1997-2000

40-79

2263

urban

No

Bestcorrected

blind, low vision

Japan

local

2000-2001

40-99

2977

urban

No

Bestcorrected

blind, low vision

Japan

local

2005-2006

40-99

3762

rural

No

Presenting

blind, low vision

Jordan*

local

2010-2012

6-14

3200

urban

No

blind

Jordan*

local

2012

50-99

3638

both

Yes

Bestcorrected Presenting

Kenya

local

2002-2003

0-89

urban

No

Presenting

blind, low vision

Kenya

local

2005

50-99

3503

both

Yes

Presenting

blind, low vision

Kenya

local

2007

50-99

3376

rural

Yes

Presenting

blind, low vision

Kenya

local

NS

0-99

rural

No

Presenting

blind, low vision

Fotouhi, A., H. Hashemi, et al. (2007). The prevalence of refractive errors among schoolchildren in Dezrul, Iran. British Journal of Ophthalmology 91(3): 287-292.

Emamian MH, Zeraati H, Majdzadeh R, Shariati M, Hashemi H, Fotouhi A. The gap of visual impairment between economic groups in Shahroud, Iran: a Blinder-Oaxaca decomposition. Am J Epidemiol. 2011 Jun 15;173(12):1463-7.

Rajavi Z, Katibeh M, Ziaei H, Fardesmaeilpour N, Sehat M, Ahmadieh H, Javadi MA. Rapid assessment of avoidable blindness in Iran. Ophthalmology.

2011 Sep;118(9):1812-8 Razavi H, Kuper H, Rezvan F, Amelie K, Mahboobi-Pur H, Oladi MR, Muhit M, Hashemi H. 2010. Prevalence and causes of severe visual impairment and blindness among children in the lorestan province of iran, using the key informant method. Ophthalm Feghhi M, Khataminia G, Ziaei H, Latifi M. 2009. Prevalence and causes of blindness and low vision in Khuzestan Province, Iran. Journal of Ophthalmic and vision research; 4 (1): 29-34.

Hashemi H, Khabazkhoob M, Emamian M, Shariata M, Fotouhi A. Visual impairment in the 40 to 64 year old population of Shahroud, Iran. 2012. Eye; 26: 1071-1077.

Cedrone, C., F. Ricci, et al. (2007). Age-specific changes in the prevalence of best-corrected visual impairment in an Italian population. Ophthalmic Epidemiology 14(5): 320-326.

Cedrone, C., C. Nucci, et al. (2005). Prevalence of blindness and low vision in an Italian population: a comparison with other European studies. Eye 20(6): 661-667.

Seland, Vingerling,Augood, Bentham, Chakravarthy et al. (2009) Visual Impairment and quality of life in the Older European Population, the EUREYE study Act Ophth 2009 Iwano, M., H. Nomura, et al. (2004). Visual Acuity in a Communitydwelling Japanese Population and Factors Associated with Visual Impairment.

Japanese Journal of Ophthalmology 48(1): 37-43.

Iwase, A., M. Araie, et al. (2006). Prevalence and causes of low vision and blindness in a Japanese adult population: the Tajimi Study. Ophthalmology 113(8): 1354-62.

Nakamura Y, Tomidokoro A, Sawaguchi S, Sakai H, Iwase A, Araie M. Prevalence and causes of low vision and blindness in a rural Southwest Island of Japan: the Kumejima study. Ophthalmology. 2010 Dec;117(12):2315-21 Mousa AMV, Suha AEM., (2014) Eye Diseases in Children in Jordan. J Pak Med Assoc;64(1):13-5 Rabiu MM, Al Bdour MD, Abu Ameerh MA, Jadoon MZ.Prevalence of blindness and diabetic retinopathy in northern Jordan. Eur J Ophthalmol. 2015 Jul-Aug;25(4):320-12 Ndegwa 2006 Prevalence of visual impairment and blindness in a Nairobi urban population Ophthalmology p69-72 Mathenge 2007 Rapid assessment of avoidable blindness in Nakuru district Kenya (Kenya -Nukuru RAAB) Ophthalmology p 599-605 Karimurio, Sheila, Gichangi, Adala and Huguet 2008 Rapid Assessment of Cataract Surgical Services in Embu District Kenya, East African Journal of Ophthalmology 13 p 19-25 Whitfield 1990 Blindness and eye disease in Kenya;ocular status survey results from the Kenya Rural Blindness Prevention Project Br J Ophth p333-344

23

Core visual acuity level

No

Presenting or bestcorrected Both

blind, low vision

Country

Coverage

Kenya*

local

Lao Peopleâ&#x20AC;&#x2122;s Democratic Republic*

Year (NS = not specified) 2007-2008

Age range

Total examined

Urban rural

50-99

4381

urban

subnational 2009

6-11

2899

Lebanon

national

24

Core visual acuity level

Reference

Yes

Presenting or bestcorrected Presenting

blind, low vision

both

No

Presenting

blind, low vision

10148

both

No

Presenting

blind, low vision

50-99

8190

both

Yes

Both

blind, low vision

subnational 2010

50-99

3157

both

Yes

Presenting

blind, low vision

Malawi

local

1983

6-99

1664

rural

No

blind, low vision

Malawi

local

2009-2010

50-99

3583

rural

Yes

Bestcorrected Presenting

Malaysia

local

1993-1994

18-99

282

rural

No

Bestcorrected

blind, low vision

Malaysia

national

1996-1997

0-99

18027

both

No

Presenting

blind, low vision

Malaysia

local

2000

40-99

311

rural

No

Presenting

blind, low vision

Malaysia

local

2003

7-15

4629

urban

No

Both

blind, low vision

Malaysia

local

2004-2006

40-80

3280

urban

No

Both

blind, low vision

Mali

local

1990

0-99

5871

rural

No

Bestcorrected

blind

Mali

subnational 2002

50-99

both

Yes

Presenting

blind, low vision

Mauritania

local

50-99

urban

Yes

Presenting

blind, low vision

Mexico

subnational 2005-2006

50-99

3764

both

Yes

Both

blind, low vision

Mexico Moldova*

subnational 2010 national 2012

50-99 50-99

2864 3877

both both

Yes Yes

Both Presenting

blind, low vision blind, low vision

Mathenge W, Basawrous A et al., (2013) Prevalence of Age-Related Macular Degeneration in Nakuru, Kenya: A Cross-Sectional Population-Based Study.

PLoS Med 10(2):e1001397 Casson RJ, Kahawita S, Kong A, Muecke J, Sisaleumsak S, Visonnavong V. Exceptionally low prevalence of refractive error and visual impairment in schoolchildren from Lao Peopleâ&#x20AC;&#x2122;s Democratic Republic. Ophthalmology. 2012 Oct;119(10):2021-7.

Mansour, A. M., K. Kassak, et al. (1997). National survey of blindness and low vision in Lebanon. British Journal of Ophthalmology 81(10): 905-6.

Rabiu MM, Jenf M, Fituri S, Choudhury A, Agbabiaka I, Mousa A.Prevalence and causes of visual impairment and blindness, cataract surgical coverage and outcomes of cataract surgery in Libya. Ophthalmic Epidemiol. 2013;20(1):2632.

Randrianaivo JB, Anholt RM2, Tendrisoa DL1, Margiano NJ1, Courtright P3, Lewallen S3.Blindness and cataract surgical services in Atsinanana region, Madagascar. Middle East Afr J Ophthalmol. 2014 Apr-Jun;21(2):153-7.

Chirambo 1986 Blindess and visual impairment in southern Malawi Bulletin of the WHO p567-574 Kalua K, Lindfield R, Mtupanyama M, Mtumodzi D, Msiska V. Findings from a rapid assessment of avoidable blindness (RAAB) in Southern Malawi. PLoS One. 2011 Apr 25;6(4):e19226.

Zainal, M., L. Masran, et al. (1998). Blindness and visual impairment amongst rural Malays in Kuala Selangor, Selangor. Medical Journal of Malaysia 53(1): 46-50.

Zainal, M., S. M. Ismail, et al. (2002). Prevalence of blindness and low vision in Malaysian population: results from the National Eye Survey 1996. British Journal of Ophthalmology 86(9): 951-6.

Reddy, S. C., L. Rampal, et al. (2004). Prevalence and causes of visual impairment and blindness in a rural population in Sepang district, Selangor.

Medical Journal of Malaysia 59(2): 212-7.

Goh PP, Abqariyah Y, Pokharel GP, Ellwein LB.: Refractive error and visual impairment in school-age children in Gombak district, Malaysia. 2005.

American Academy of Ophthalmology. 112, 678-685.

Wong, T. Y., E. W. Chong, et al. (2008). Prevalence and causes of low vision and blindness in an urban malay population: the Singapore Malay Eye Study.

Archives of Ophthalmology 126(8): 1091-9.

Kortlang C, Koster JCA, Coulibaly S, Dubbeldam RP.: Prevalence of blindness and visual impairment in the region of Segou, Mali. A baseline survey for a primary eye care programme. 1996. Tropical medicine and International Health. 1 (3) 314-319 Ceccon JF: Results of rapid assessment of cataract surgical services in Koulikoro, Mali. 2002. Institute of African Tropical Ophthalmology, Bamako Mali.

Ahmedou SE. Results of rapid assessment of cataract surgical services in urban Nouackchott, Mauritania. 2001. Service Ophthalmologie, MOH, Nouackchott, Mauritania.

Pedro Gomez cited in Limburg et al. Cataract in Latin America Rev Panam Salud Publica/Pan Am J Public Health 25(5), 2009 Sarah Polack RAAB in Chiapas, Mexico (2010) unpublished Zatic T. Rapid assessment of avoidable blindness and diabetic retinopathy in Republic of Moldova. Br J Ophthalmol. 2015 Jun;99(6):832-7

3-98

Libyan Arab Jamahiriya*

subnational 2010

Madagascar*

1995

2002

/

Rapid

blind, low vision

Country

Coverage

Age range

Total examined

Urban rural

Mongolia

Year (NS = not specified) subnational 1991-1992

40-99

4345

both

Mongolia

subnational 1995

40-87

942

Morocco

national

1992

0-99

Mozambique* Myanmar

local local

2012 2001

Myanmar

local

Nepal

national

Nepal

25

Core visual acuity level

Reference

No

Presenting or bestcorrected Both

blind

both

No

Presenting

blind

8878

both

No

blind, low vision

50-99 50-99

3386

both both

No Yes

Bestcorrected Both Presenting

blind, low vision blind, low vision

2005

40-99

2076

rural

No

Both

blind, low vision

1980-1981

0-99

39887

both

No

Bestcorrected

blind

subnational 1997

5-15

4803

both

No

Both

low vision

Nepal

local

1998

5-15

4802

rural

No

Both

blind, low vision

Nepal

local

2002

45-99

5002

rural

No

Both

blind

Nepal

local

2006

50-99

5138

rural

Yes

Both

blind, low vision

Nepal

local

2006

50-99

4717

rural

Yes

Both

blind, low vision

Nepal

local

2008

50-99

1171

rural

Yes

Both

blind, low vision

Nepal Nepal Nepal

local 2008 local 2008 subnational 2008

50-99 50-99 50-99

2513 2895 3613

rural both both

Yes Yes Yes

Both Both Both

blind, low vision blind, low vision blind, low vision

Nepal Nepal Nepal Nepal Nepal

local local local local local

50-99 50-99 50-99 50-99 50-99

2914 3041 2993 2921 2990

rural rural rural rural rural

Yes Yes Yes Yes Yes

Both Both Both Both Both

blind, blind, blind, blind, blind,

Baasanhu J, Johnson G J, Burendei G, Minassian D C : Prevalence and causes of blindness and visual impairment in Mongolia: a survey of populations aged 40 years and older. 1994. Bulletin of the World Health Organization. 72(5), 771-776 Foster P J, Baasanhu J, Alsbirk P H, Munkhbayar D, Uranchimeg D, Johnson G J, : Glaucoma in Mongolia. A Population-Based Survey in Hovsgol Provence, Northern Mongolia. 1996. Arch Opthalmol. 114, 1235-1241 Annon (1994). Prevention of blindness (PBL) : prevalence and causes of blindness and low vision. Weekly Epidemiological Record 69(18): 129-161. rapid repository Limburg H, Maung N, Khin Aye Soe, Mynt Than Win. Study report on rapid assessment of cataract surgical services in Hinthada Township, Union of Myanmar. Ministry of Health, Department of Health, Trachoma Control and Prevention of Blindness Progr Casson, R. J., H. S. Newland, et al. (2007). Prevalence and Causes of Visual Impairment in Rural Myanmar. The Meiktila Eye Study. Ophthalmology 114(12): 2302-2308.

Brilliant LB, Pokhrel RP, Grasset NC, Lepkowski JM, Kolstad A, Hawks W, Pararajasegaram R, Brilliant GE, Gilbert S, Shrestha SR, Juo J.: Epidemiology of blindness in Nepal. 1985. Bulletin of the World Health Organisation.

63(2), 375-386.

Pokharel GP, Negrel AD, Munoz SR, Ellwein LB. 2000. Refractive error study in children: Results from Mechi Zone, Nepal. American Journal of Ophthalmology 129(4):436-444.

Gilbert CE et al. Prevalence and causes of functional low vision in school-age children: Results from standardized population surverys in Asia, Africa, and Latin America Investigative Ophthalmology & Visual Science, March 2008, Vol. 49, No. 3 Sapkota, Y. D., G. P. Pokharel, et al. (2006). Prevalence of blindness and cataract surgery in Gandaki Zone, Nepal. British Journal of Ophthalmology 90(4): 411-6.

Sherchan A, Kandel RP, Sharma MK, Sapkota YD, Aghajanian J, Bassett KL. Blindness prevalence and cataract surgical coverage in Lumbini Zone and Chetwan District of Nepal. Br J Ophthalmol. 2010 Feb;94(2):161-6.

Sapkota YD, Sunuwar M, Naito T, Akura J, Adhikari HK. The prevalence of blindness and cataract surgery in rautahat district, Nepal. Ophthalmic Epidemiol. 2010 Mar;17(2):82-9.

Dulal S, Sapkota Y. Prevalence of blindness and visual impairment and its causes among people aged 50 years and above in Karnali Zone, Nepal.

NEPAL SETI & MAHAKALI ZONES RAPID DATA NEPAL KOSHI ZONE RAPID DATA Reeta Gurung (2008), RAAB in Bagmati and Janakpur zone, Nepal. Unpublished NEPAL SAGARMATA ZONE RAPID DATA NEPAL MECHI ZONE RAPID DATA NEPAL BHERI ZONE RAPID DATA NEPAL RAPTI ZONE RAPID DATA NEPAL DHAULAGIRI ZONE RAPID DATA

2008 2009 2009 2010 2010

/

Rapid

low low low low low

vision vision vision vision vision

Country

Coverage

Age range

Total examined

Urban rural

local

Year (NS = not specified) NS

Nepal

40-99

4003

both

No

Nepal*

local

2007

0-15

466

both

No

Nepal*

local

2007-2010

3-22

1802

both

Nepal*

local

NS

4-18

140

Netherlands

local

1990-1993

55-99

Netherlands

local

1997-1999

85-99

Nigeria

local

1991

Nigeria

/

Rapid

Presenting or bestcorrected Both

Core visual acuity level

Reference

blind, low vision

Thapa SS, Berg RV, Khanal S, Paudyal I, Pandey P, Maharjan N, Twyana SN, Paudyal G, Gurung R, Ruit S, Rens GH. 2011. Prevalence of visual impairment, cataract surgery and awareness of cataract and glaucoma in Bhaktapur district of Nepal: the Bh Sherpa D, Pant C, Joshi N. Ocular morbidity among primary school children of Dhulikhel, Nepal. Nepal J Ophthalmology 2011; 3 (2): 172-176.

Marasini S, Sharma R, Sthapit PR, Sharma D, Koju U, Thapa G, Nepal BP. Refractive errors and visual anomalies in school children in the Kavrepalanchowk District. Kathmandu Univ Med J (KUMJ). 2010 Oct-Dec;8(32):362-6 Adhikari S., (2013) Myopia in school children from high mountain region of Nepal. J Ophthalmol; 5 (10):246-251 Klaver, C. C., R. C. Wolfs, et al. (1998). Age-specific prevalence and causes of blindness and visual impairment in an older population: the Rotterdam Study.

Archives of Ophthalmology 116(5): 653-8.

Gussekloo, J., A. J. de Craen, et al. (2005). Sensory impairment and cognitive functioning in oldest-old subjects: the Leiden 85+ Study. American Journal of Geriatric Psychiatry 13, 781-6.

Adeoye A.: Survey of blindness in rural communities of south-western Nigeria.

1996. Tropical Medicine and International Health. 1 (5) 672-676.

Ezepue UF.: Magnitude and causes of blindness and low vision in Anambra State of Nigeria (results of 1992 point prevalence survey). 1997. Public Health.

111 305-309.

Abdu L.: Prevalence and causes of blindness and low vision in Dambatta local government area, Kano State Nigeria. 2002 Nigerian Journal of Medicine.

11(3) 108-112.

Rabiu, M. (2001). Cataract blindness and barriers to uptake of cataract surgery in a rural community of northern Nigeria. British Medical Journal 85(7): 776.

Patrick-Ferife G, Ashaye AO, Osuntokun OO. : Rapid assessment of cataract blindness among Ughelli clan in an urban/rural district of Delta State, Nigeria.

2005. Annals of African Medicine. 4 (2) 52-57.

Adegbehingbe BO, Majengbasan TO.: Ocular health status of rural dwellers in south-western Nigeria. 2007. Aust J Rural Health. 15 269-272.

Ajaiyeoba AI, Isawumi MA, Adeoye AO, Oluleye TS.: Pattern of eye disease and visual impairment among students in southwestern Nigeria. 2007. Int Ophthalmol. 27 287-292.

Muhammad N, Mansur RM, Dantani AM, Elhassan E, Isiyaku S. Prevalence and causes of blindness and visual impairment in sokoto state, Nigeria: baseline data for vision 2020: the right to sight eye care programme.. Middle East Afr J Ophthalmol. 20 Mpyet C, Ogoshi C, Goyol M. : Prevalence of Trachoma in Yobe State, NorthEastern Nigeria. 2008. Ophthalmic Epidemiology. 15, 303-307.

Kyari, F., M. V. S. Gudlavalleti, et al. (2009). Prevalence of Blindness and Visual Impairment in Nigeria: The national blindness and visual impairment survey. Investigative Ophthalmology & Visual Science 50(5): 2033 Oluleye TS.: Cataract Blindness and Barriers to Cataract Surgical Intervention in Three Rural Communities of Oyo State, Nigeria. 2004 13 (2) 156-160.

Adeoti CO.: Prevalence and causes of blindness in a tropical African population. 2004. WAJM. 23 (3). 249-252.

Onakpoya OH, Adeoye AO, Akinsola FB, Adegbehingbe.: Prevalence of blindness and visual impairment in Atakunmosa West Local Government Area of southwestern Nigeria. 2007. Tanzania Health Research Bulletin. 9 (2) 126-131.

No

Bestcorrected Both

blind, low vision

rural

No

Presenting

blind, low vision

urban

No

Bestcorrected

blind, low vision

459

both

No

Presenting

low vision

0-99

2921

rural

No

Both

blind

subnational 1992

0-99

1752

both

No

Bestcorrected

blind, low vision

Nigeria

local

0-99

3332

both

No

Presenting

blind, low vision

Nigeria

subnational 1999

40-99

1461

rural

Yes

Presenting

blind, low vision

Nigeria

local

2001

50-99

684

both

Yes

Presenting

blind

Nigeria

local

2002

8-92

2201

rural

No

Presenting

blind

Nigeria

local

2002

4-24

1144

both

No

Presenting

blind, low vision

Nigeria

local

2005

0-99

4848

rural

No

Presenting

blind, low vision

Nigeria

subnational 2006

1-97

3357

rural

No

Presenting

blind

Nigeria

national

2007

40-99

13599

both

No

Both

blind, low vision

Nigeria

local

NS

50-99

477

rural

Yes

Presenting

blind

Nigeria

local

NS

0-99

3204

rural

No

Presenting

blind

Nigeria

local

NS

0-99

1248

rural

No

Presenting

blind, low vision

1995

low vision

26

Country

Coverage

Nigeria*

local

Nigeria*

Year (NS = not specified) 2001

Age range

Total examined

Urban rural

40-99

2044

rural

subnational 2005

50-99

1183

Nigeria*

local

2006

50-99

Nigeria*

local

NS

Nigeria*

Core visual acuity level

Reference

Yes

Presenting or bestcorrected Presenting

blind, low vision

both

Yes

Presenting

blind, low vision

2565

urban

Yes

Both

blind, low vision

0-99

1513

rural

No

low vision

subnational NS

50-99

4115

both

Yes

Bestcorrected Presenting

blind

Nigeria*

subnational NS

60-99

630

both

No

Presenting

low vision

Norway

local

65-99

737

urban

No

Bestcorrected

blind, low vision

Norway*

subnational 2007-2008

38-87

6331

both

No

Bestcorrected

low vision

Norway*

subnational 2007-2008

65-87

2631

both

No

Bestcorrected

low vision

Occupied Palestinian Territory Occupied Palestinian Territory Oman

local

1982-1983

0-99

9054

both

No

Presenting

blind, low vision

MM Rabiu, CP Ozemela, DI Apiafi. Gathering Baseline Data for a Rural Cataract Surgical Outreach Service in Igabi District, Nigeria Kolawole OU, Ashaye AO, Mahmoud AO, Adeoti CO. Cataract blindness in Osun state, Nigeria: results of a survey. Middle East Afr J Ophthalmol. 2012 Oct;19(4):364-74 Rabiu MM, Muhammed N. Rapid assessment of cataract surgical services in Birnin-Kebbi local government area of Kebbi State, Nigeria. Ophthalmic Epidemiol. 2008 Nov-Dec;15(6):359-67 Ejimadu C, Adio A. The burden of low vision in farming communities in SouthSouth Nigeria. Nigerian Journal of Medicine 2012; 21 (2): 218-222.

Odugbo OP, Mpyet CD, Chiroma MR, Aboje AO. Cataract blindness, surgical coverage, outcome, and barriers to uptake of cataract services in Plateau State, Nigeria. Middle East Afr J Ophthalmol. 2012 Jul-Sep;19(3):282-9 Abegunde K, Owoaje E. 2013. Health problems and associated risk factors in selected urban and rural elderly population groups of South-West Nigeria.

Annals African Medicine 12 (2) 90-97.

Seland, Vingerling,Augood, Bentham, Chakravarthy et al. (2009) Visual Impairment and quality of life in the Older European Population, the EUREYE study Act Ophth 2009 Bertelsen G, Erke M, von Hanno T, et al. The Tromso eye study: study design, methodology and results on visual acuity and refractive errors. Acta Ophthalmol. 2013: 91: 635-642.

Erke M, Bertelsen G, Peto T, et al. Prevalence of age-related macular degeneration in elderly caucasians: the Tromso eye study. Ophthalmology. 2012; 119 (9); 1737-1743.

Thomson I M, Chumbley L C. Eye disease in the West Bank and Gaza strip.

Br J Ophthalmol 1984;68:598-602

national

2008

50-99

3579

both

Yes

Both

blind, low vision

national

1996-1997

0-99

11417

both

No

Presenting

blind

Pakistan

local

1998

40-99

1106

rural

No

Presenting

blind, low vision

Pakistan Pakistan

national local

2001-2003 2003

30-99 5-15

16507 5110

both urban

No No

Presenting Presenting

blind, low vision blind, low vision

Pakistan

local

NS

50-99

1505

both

Yes

Both

blind, low vision

Pakistan

local

NS

50-99

1549

rural

Yes

Bestcorrected

blind

Panama* Papua New Guinea

local local

2012-2014 2004-2005

50-99 50-99

4125 1174

both both

Yes Yes

Both Presenting

blind, low vision blind, low vision

NS

/

Rapid

27

Chiang F, Kuper H, Lindfield R, Keenan T, Seyam N, Magauran D, Khalilia N, Batta H, Abdeen Z, Sargent N. Rapid assessment of avoidable blindness in the Occupied Palestinian Territories. PLoS One. 2010 Jul 29;5(7):e11854.

Khandekar, R., A. J. Mohammed, et al. (2004). Coverage of cataract surgery per person and per eye: review of a community-based blindness survey in Oman. Ophthalmic Epidemiology 11(4): 291-9.

Ahmad K, Khan MD, Qureshi MB, Munami S, Shah RA, Rasheed H, Jamali B, Baluch A, Khan MA.; Prevalence and causes of blindness and low vision in a rural setting in Pakistan. 2005. Ophthalmic Epidemiology. 12(1), 19-23.

Bourne Pakistan national Eye Survey Microdata (2001) Shaikh, S. P. and T. M. Aziz (2005). Pattern of eye diseases in children of 5-15 years at Bazzertaline area (South Karachi) Pakistan. Journal of the College of Physicians and Surgeons Pakistan 15(5): 291-294.

Haider S, Hussain A, Limburg H, 2003. Cataract blindness in Chakwal District, Pakistan: results of a survey. Ophthalmic Epidemiology 10(4):249-58.

Anjum KM, Qureshi MB, Khan MA, Jan N, Ali A, Ahmad K, Khan MD.: Cataract blindness and visual outcome of cataract surgery in a tribal area in Pakistan. 2006. British Journal of Ophthalmology. 90, 135-138. report Garap, J. N., S. Sheeladevi, et al. (2006). Blindness and vision impairment in the elderly of Papua New Guinea. Clinical and Experimental Ophthalmology 34(4): 335-341.

Country

Coverage

Age range

Total examined

Urban rural

national

Year (NS = not specified) 1999

Paraguay

50-99

2136

both

Paraguay Peru

national local

2011 2002

50-99 50-99

2862 4782

Peru Philippines

national local

2011 2006

50-99 50-99

Qatar

national

2009

50-99

Republic Korea*

of

national

2008-2010

30-95

Republic Korea*

of

national

2010-2011

40-99

local

Core visual acuity level

Reference

Yes

Presenting or bestcorrected Both

blind, low vision

both rural

Yes Yes

Both Both

blind, low vision blind, low vision

4852 3177

both rural

Yes Yes

Both Presenting

blind, low vision blind, low vision

2433

both

Yes

Both

blind, low vision

both

No

Bestcorrected

blind, low vision

both

No

Bestcorrected

blind, low vision

urban

Yes

Presenting

blind, low vision

Duerksen R, Limburg H, Carron JE, Foster A. Cataract blindness in Paraguayresults of a national survey.

Ophthalmic Epidemiol.

2003; 10(5):34957.

PARAGUAY 2011 RAPID DATA Pongo Aguila, L., R. Carrion, et al. (2005). Cataract blindness in people 50 years old or older in a semirural area of northern Peru. [Spanish]. Revista Panamericana de Salud Publica/Pan American Journal of Public Health 17(56): 387-393.

PERU RAPID DATA Eusebio, C., H. Kuper, et al. (2007). Rapid assessment of avoidable blindness in Negros Island and Antique District, Philippines. British Journal of Ophthalmology 91(12): 1588-1592.

Al Gamra H, Al Mansouri F, Khandekar R, Elshafei M, Al Qahtani O, Singh R, Hashim SP, Mujahed A, Makled A, Pai A. Prevalence and causes of blindness, low vision and status of cataract in 50 years and older citizen of Qatar-a community based sur Rim THT, Nam JS et al., (2014) Prevalence and risk factors of visual impairmentand blindness in Korea: the Fourth Korea National Health and Nutrition Examination Survey in 20082025 Cho B, Heo JW et al., (2013) Prevalence and Risk Factors of Age-Related Macular Degeneration in Korea: The Korea National Health and Nutrition Examination Survey 20102011. Invest Ophthalmol Vis Sci;55:1101-1110 Branchevskiy S. 2008, RAAB Samara district Russia - unpublished report

7899

/

Rapid

28

Russian Federation Rwanda

2008

50-99

subnational 2006

50-99

2206

both

Yes

Presenting

blind, low vision

Saudi Arabia*

subnational 2011

50-99

3052

both

Yes

Presenting

blind, low vision

Sierra Leone Singapore

national local

50-99 40-79

2976 1152

both urban

Yes No

Both Bestcorrected

blind, low vision blind, low vision

Singapore

subnational NS

3-6

3009

urban

No

Presenting

low vision

South Africa

local

1992

40-99

987

rural

No

Presenting

blind

South Africa

local

1998-1999

40-99

1005

rural

No

Presenting

blind

South Africa

local

2002

5-15

4679

both

No

Both

blind, low vision

South Africa

local

NS

0-99

6090

rural

No

Presenting

blind, low vision

2010-2011 1997-1998

Mathenge 2007 Rapid assessment of avoidable blindness in Western Rwanda; Blindness in a postconflict setting PLoS Medicine p1187-1193 Al Ghamdi AH, Rabiu M, Hajar S, Yorston D, Kuper H, Polack S.Rapid assessment of avoidable blindness and diabetic retinopathy in Taif, Saudi Arabia.

Br J Ophthalmol. 2012 Sep;96(9):1168-72.

SIERRA LEONE RAPID DATA Saw, S. M., P. J. Foster, et al. (2004). Causes of blindness, low vision, and questionnaire-assessed poor visual function in Singaporean Chinese adults: The Tanjong Pagar Survey. Ophthalmology 111(6): 1161-8.

Dirani M, Zhou B, Hornbeak D, Chang BC, Gazzard G, Chia A, Ling Y, Selvaraj P, Young TL, Varma R, Wong TY, Saw SM. Prevalence and causes of decreased visual acuity in Singaporean Chinese preschoolers. Br J Ophthalmol.

2010 Dec;94(12):1561-5.

Salmon JF, Mermoud A, Ivey A, Swanevelder SA, Hoffman M.: The prevalenceof primary angle closure glaucoma, and open angle glaucoma in Mamre, Western Cape, South Africa. 1993. Arch Ophthalmol. 111 1263-1269.

Rotchford AP, Johnson GJ.: Glaucoma in Zulus. A Population-Based Crosssectional Survey in a Rural District in South Africa. 2002. Arch Ophthalmol.

120. 471-478.

Gilbert CE et al.(2008) Prevalence and causes of functional low vision in schoolage children: Results from standardized population surverys in Asia, Africa, and Latin America Investigative Ophthalmology & Visual Science, Vol. 49, No. 3 Cook CD, Knight SE, Crofton-Briggs I.: Prevalence and causes of low vision and blindness in northern Kwazulu. 1993. SAMJ. 83 590-593.

Country

Coverage

29

Age range

Total examined

Urban rural

local

Year (NS = not specified) 2010

South Africa*

50-99

2744

urban

No

Spain

local

2007

40-79

510

urban

No

Bestcorrected

blind, low vision

Spain

local

NS

64-97

1144

both

No

Bestcorrected

blind, low vision

Sri Lanka

local

2006-2007

40-99

1375

rural

No

Bestcorrected

blind, low vision

Sudan

local

2005

5-99

2499

rural

No

Presenting

blind, low vision

Taiwan

local

1993-1995

50-99

2038

urban

No

Bestcorrected

low vision

Taiwan

national

2002

65-99

3160

both

No

Bestcorrected

blind, low vision

Taiwan*

local

NS

65-99

2316

both

No

Bestcorrected

blind, low vision

Thailand

national

1994-1995

0-99

both

No

Presenting

blind, low vision

Thailand

local

1997-1998

40-99

2092

urban

No

Bestcorrected

blind, low vision

Thailand

local

1997-1999

50-99

701

urban

No

Both

blind

Timor-Leste

subnational 2005

40-99

1414

both

Yes

Presenting

blind, low vision

Timor-Leste*

national

40-99

2014

both

Yes

Presenting

blind, low vision

Tonga

subnational 1991

20-99

4056

both

No

Bestcorrected

blind, low vision

Tunisia

national

1993

0-99

3547

both

No

Presenting

blind, low vision

Turkey

subnational 1989

0-99

7497

both

No

Presenting

blind, low vision

Turkey*

local

2008-2009

6-14

21062

rural

No

Both

blind

Turkmenistan

national

2000-2001

50-99

6011

both

Yes

Presenting

blind, low vision

Uganda

local

2007

50-99

both

Yes

Presenting

blind, low vision

2009-2010

/

Rapid

Presenting or bestcorrected Presenting

Core visual acuity level

Reference

blind, low vision

Cockburn N, Steven D, Lecunoa K, et al. (2012) Prevalence, Causes and SocioEconomic Determinants of Vision Loss in Cape Town, South Africa. PLoS ONE 7(2): e30718. doic:10.1371/journal.pone.0030718 Anton A et al. Epidemiology of Refractive Errors in an Adult European Population: The Segovia Study (Spain) 2009 Ophth Epi, Vol. 16, No. 4 , Pages 231-237 Esteban, J. J., M. S. Martinez, et al. (2008). Visual impairment and quality of life: gender differences in the elderly in Cuenca, Spain. Quality of Life Research 17, 37-45.

Edussuriya K, Sennanayake S, Senaratne T, Marshall D, Sullivan T, Selva D, Casson RJ. The prevalence and causes of visual impairment in central Sri Lanka the Kandy Eye study. Ophthalmology. 2009 Jan;116(1):52-6.

Ngondi 2006 Prevalence and causes of blindness and low vision in Southern Sudan PLoS Medicine p2416-2426 J Liu, C Cheng, S Chen, F Lee. Visual impairment in a Taiwanese population: Prevalence, causes, and socioeconomic factors. Ophthalmic epidemiology.2001;8:339-358 Tsai, C. Y., L. C. Woung, et al. (2005). The current status of visual disability in the elderly population of Taiwan. Japanese Journal of Ophthalmology 49(2): 166-172.

Chen N, Huang T, Tsai R, Sheu M. Prevalence and causes of visual impairment in elderly Amis aborigines in eastern Taiwan. Japanese Journal of Ophthalmology 2012; 56 ; 624-630.

Prompubesara and Wongwetsawat Third National Survey on blindness and low vision in Thailand 1994 UNPUBLISHED Singalavanija, A., A. Metheetrairut, et al. (2001). Ocular diseases and blindness in elderly Thais. Journal of the Medical Association of Thailand 84(10): 1383-8.

Bourne, R. R., P. Sukudom, et al. (2003). Prevalence of glaucoma in Thailand: a population based survey in Rom Klao District, Bangkok. British Journal of Ophthalmology 87(9): 1069-74.

Ramke, J., A. Palagyi, et al. (2007). Prevalence and causes of blindness and low vision in Timor-Leste. British Journal of Ophthalmology 91(9): 1117-1121.

Ramke J, Brian G, Naduvilath T. Refractive error and presbyopia in timorleste: the impact of 5 years of a national spectacle program.Invest Ophthalmol Vis Sci. 2012 Jan 25;53(1):434-9.

Newland, Woodward, et al. (1994). Epidemiology of blindness and visual impairment in the kingdom of Tonga. British Journal of Ophthalmology 78(5): 344-8.

Ayed S, Ngrel A-D, Nabli M, Jebri A M, Siddhom J. Prevalence et causes de la cecit en Republique Tunisienne. Cahiers Sante 1998;8:275-282.

Negrel, A. D., D. C. Minassian, et al. (1996). Blindness and low vision in southeast Turkey. Ophthalmic Epidemiology 3(3): 127-34.

Caca I, Cingu A, Sahin A, et al. 2013. Amblyopia and refractive errors among school aged children with low socioeconomic status in southeastern Turkey.

Journal of Paediatric Ophthalmology and strabismus; 50 (1); 37-43.

Amansakhatov S, Volokhovskaya Z P, Afanasyeva A N, Limburg H: Cataract blindness in Turkmenistan: results of a national survey. 2002. British Journal of Ophthalmology. 86, 1207-1210 Uganda 2007 RACCS unpublished report, no authors, Masaka

Country

Coverage

Age range

Total examined

Urban rural

local

Year (NS = not specified) NS

Uganda

13-99

4076

rural

Uganda* Uganda* United Kingdom

local local national

2012 2013 1980

50-99 50-99 10-12

3729 3827 12853

United dom United dom

King-

local

1982-1984

75-99

King-

national

1994-1995

United dom United dom

King-

local

King-

30

Core visual acuity level

Reference

No

Presenting or bestcorrected Presenting

blind, low vision

both both both

Yes Yes No

Both Both Presenting

blind, low vision blind, low vision low vision

529

both

No

blind, low vision

65-99

1362

both

No

Bestcorrected Presenting

low vision

NS

65-99

207

urban

No

Presenting

blind, low vision

local

NS

65-99

629

urban

No

Bestcorrected

blind, low vision

United Republic of Tanzania United Republic of Tanzania United Republic of Tanzania

local

1986

7-99

1827

rural

No

blind, low vision

local

2007

50-99

both

Yes

Bestcorrected Presenting

Mbulaiteye 2002 Evaluation of E optotypes as a screening test and the prevalence and causes of visual loss in a rural population of SW Uganda. Ophthalmic Epidemiology p251-262 report report Stewart-Brown, S. and N. Butler (1985). Visual acuity in a national sample of 10 year old children. Journal of Epidemiology & Community Health 39(2): 107-12.

Gibson, J. M., J. R. Lavery, et al. (1986). Blindness and partial sight in an elderly population. British Journal of Ophthalmology 70, 700-5. van der Pols, J. C., C. J. Bates, et al. (2000). Visual acuity measurements in a national sample of British elderly people. British Journal of Ophthalmology 84, 165-70.

Wormald, R. P., L. A. Wright, et al. (1992). Visual problems in the elderly population and implications for services.[see comment]. BMJ 304, 1226-9.

Seland, Vingerling,Augood, Bentham, Chakravarthy et al. (2009) Visual Impairment and quality of life in the Older European Population, the EUREYE study Act Ophth 2009 Rapoza 1991 Prevalence and causes of vision loss in central Tanzania International Ophthalmology p 123-9 Tanzania 2007 - RACSS unpublished report, Kyela District

local

2007

50-99

rural

No

Presenting

blind, low vision

United Republic of Tanzania

subnational 2007

50-99

both

Yes

Presenting

blind, low vision

United Republic of Tanzania* United States of America United States of America United States of America United States of America Uruguay Vanuatu

local

2007

50-99

3160

both

Yes

Presenting

blind

Habiyakire, Kabona, Courtright, Lewallen (2010) Rapid Assessment of Avoidable Blindness and Cataract Surgical Services in Kilamanjaro Region, TanzaniaOphth Epi. 17(2)90-94 name(?) Rapid Assessment of avoidable blindness in Zanzibar. Submitted for MSc Community Eye Health at the London School of Hygiene and Tropical Medicine. 2007 RAAB survey of Pemba and Unguja islands, Zanzibar

local

1985-1988

40-99

5308

urban

No

blind, low vision

BALTIMORE EYE STUDY

local

1988-1990

40-89

4916

rural

No

blind, low vision

local

1993-1995

65-84

2519

urban

No

blind, low vision

Klein R, Klein BEK, Lee KE. Changes in visual acuity in a population. The Beaver Dam Eye Study. Ophthalmology 1996;103:116978.

Salisbury ES

local

1999-2000

40-99

4766

urban

No

blind, low vision

Proyecto VER

local national

2011 1989

50-99 6-99

3729 3520

both both

Yes No

Bestcorrected Bestcorrected Bestcorrected Bestcorrected Both Bestcorrected

blind, low vision blind

national

2005

50-99

3317

both

Yes

Both

blind, low vision

URUGUAY RAPID DATA Newland, H. S., M. F. Harris, et al. (1992). Epidemiology of blindness and visual impairment in Vanuatu. Bulletin of the World Health Organization 70(3): 369-72. .Primera Encuesta Nacional. Rev. Oftalmol. Venez.v.61n.2Caracasabr.2010

3436

/

Rapid

blind, low vision

Venezuela (Bolivarian Republic of) Viet Nam

subnational 2000-2002

50-99

14138

both

Yes

Both

blind, low vision

Viet Nam

subnational 2007

50-99

28033

both

Yes

Both

blind, low vision

Viet Nam*

local

50-99

1753

both

Yes

Both

blind, low vision

2007

Limburg (2008): Results of Rapid Assessment for Avoidable blindness (RAAB) in 16 provices of Vietnam Limburg (2008): Results of Rapid Assessment for Avoidable blindness (RAAB) in 16 provices of Vietnam report

Country

Coverage

Age range

Total examined

Urban rural

Yemen Yemen Zambia*

Year (NS = not specified) local 2009 local 2009 subnational 2010

50-99 50-99 50-99

1836 1789 3629

rural rural both

Zambia*

subnational 2011

50-99

3629

Zimbabwe

local

60-99

278

NS

/

Rapid

Core visual acuity level

Reference

Yes Yes Yes

Presenting or bestcorrected Both Both Presenting

blind, low vision blind, low vision low vision

both

Yes

Both

blind, low vision

both

No

Presenting

blind

YEMEN LAHJ RAPID ASSESSMENT YEMEN AMRAN RAPID ASSESSMENT Lindfield R, Griffiths U et al., (2012) A Rapid Assessment of Avoidable Blindness in Southern Zambia. PLoS ONE 7(6): e38500 Lindfield R, Griffiths U, Bozzani F, Mumba M, Munsanje J. A rapid assessment of avoidable blindness in Southern Zambia. PLoS One. 2012;7(6):e38483.

Allain TJ, Wilson AO, Gomo ZAR, Mushangi E, Senzanje B, Adamchak DJ, Matenga JA.: Morbidity and disability in elderly Zimbabweans. 1997. Age and Ageing. 26 115-121.

31

Table 3. Characteristics of data sources used in the presbyopia analysis.

Country

Coverage

Year 2011

Age range 35-99

Total examined 3691

Kenya

Subnational

India

Subnational

2008-2009, 2011

35-99

2630

South Africa

Subnational

2008-2009, 2011

35-99

1939

Niger

Subnational

2008-2009, 2011

35-99

2045

Subnational

2008-2009, 2011

35-99

672

China

Subnational

2008-2009, 2011

35-99

3554

China

Subnational

2008-2009, 2011

35-99

1817

Eritrea

Subnational

2008

35-49

3171

United Republic of Tanzania India

Subnational

2004

40-99

1709

Subnational

2008

35-49

3203

Pakistan Kenya

Subnational Subnational

2007-2008

35-49 50-99

2939 4414

Nigeria

Subnational

2012

35-99

3899

Australia

Subnational

1994

40-99

3266

Mongolia

Subnational

2009

40-99

5158

India

Subnational

2011-2012

40-99

7378

Canada

Subnational

2009

40-99

768

Nepal

Subnational

2008-2009, 2011

35-99

2156

United States America

of

Reference

32

Kimani, K., et al. (2013). ”Prevalence and causes of ocular morbidity in Mbeere District, Kenya. Results of a population-based survey.” PLoS One 8(8): e70009.

He, M., et al. (2012). ”Prevalence and correction of near vision impairment at seven sites in China, India, Nepal, Niger, South Africa, and the United States.” Am J Ophthalmol 154(1): 107-116 e101., He, M., et al.

(2014). ”Age-related prevalence and met need for correctable and uncorrectable near vision impairment in a multi-country study.” Ophthalmology 121(1): 417-422.

He, M., et al. (2012). ”Prevalence and correction of near vision impairment at seven sites in China, India, Nepal, Niger, South Africa, and the United States.” Am J Ophthalmol 154(1): 107-116 e101., He, M., et al.

(2014). ”Age-related prevalence and met need for correctable and uncorrectable near vision impairment in a multi-country study.” Ophthalmology 121(1): 417-422.

He, M., et al. (2012). ”Prevalence and correction of near vision impairment at seven sites in China, India, Nepal, Niger, South Africa, and the United States.” Am J Ophthalmol 154(1): 107-116 e101., He, M., et al.

(2014). ”Age-related prevalence and met need for correctable and uncorrectable near vision impairment in a multi-country study.” Ophthalmology 121(1): 417-422.

He, M., et al. (2012). ”Prevalence and correction of near vision impairment at seven sites in China, India, Nepal, Niger, South Africa, and the United States.” Am J Ophthalmol 154(1): 107-116 e101., He, M., et al.

(2014). ”Age-related prevalence and met need for correctable and uncorrectable near vision impairment in a multi-country study.” Ophthalmology 121(1): 417-422.

He, M., et al. (2012). ”Prevalence and correction of near vision impairment at seven sites in China, India, Nepal, Niger, South Africa, and the United States.” Am J Ophthalmol 154(1): 107-116 e101., He, M., et al.

(2014). ”Age-related prevalence and met need for correctable and uncorrectable near vision impairment in a multi-country study.” Ophthalmology 121(1): 417-422.

He, M., et al. (2012). ”Prevalence and correction of near vision impairment at seven sites in China, India, Nepal, Niger, South Africa, and the United States.” Am J Ophthalmol 154(1): 107-116 e101., He, M., et al.

(2014). ”Age-related prevalence and met need for correctable and uncorrectable near vision impairment in a multi-country study.” Ophthalmology 121(1): 417-422.

Chan, V. F., et al. (2013). ”Prevalence of refractive error and spectacle coverage in Zoba Ma’ekel Eritrea: a rapid assessment of refractive error.” Ophthalmic Epidemiol 20(3): 131-137.

Burke, A. G., et al. (2006). ”Population-based study of presbyopia in rural Tanzania.” Ophthalmology 113(5): 723-727.

Marmamula, S., et al. (2009). ”Uncorrected refractive errors, presbyopia and spectacle coverage: results from a rapid assessment of refractive error survey.” Ophthalmic Epidemiol 16(5): 269-274.

Unpublished RARE survey - permission obtained from Hasan Minto Bastawrous, A., et al. (2013). ”Prevalence and predictors of refractive error and spectacle coverage in Nakuru, Kenya: a cross-sectional, population-based study.” Int Ophthalmol 33(5): 541-548.

Senyonjo, L., et al. (2014). ”Ocular morbidity and health seeking behaviour in Kwara state, Nigeria: implications for delivery of eye care services.” PLoS One 9(8): e104128.

Taylor, H. R., et al. (1997). ”Visual impairment in Australia: distance visual acuity, near vision, and visual field findings of the Melbourne Visual Impairment Project.” Am J Ophthalmol 123(3): 328-337.

Cheng, F., et al. (2015). ”Distance- and near-visual impairment in rural Chinese adults in Kailu, Inner Mongolia.” Acta Ophthalmol.

Marmamula, S., et al. (2014). ”Prevalence of spectacles use in Andhra Pradesh, India: rapid assessment of visual impairment project.” Clin Experiment Ophthalmol 42(3): 227-234.

Robinson, B., et al. (2013). ”Prevalence of visual impairment and uncorrected refractive error - report from a Canadian urban population-based study.” Ophthalmic Epidemiol 20(3): 123-130.

He, M., et al. (2012). ”Prevalence and correction of near vision impairment at seven sites in China, India, Nepal, Niger, South Africa, and the United States.” Am J Ophthalmol 154(1): 107-116 e101., He, M., et al.

(2014). ”Age-related prevalence and met need for correctable and uncorrectable near vision impairment in a multi-country study.” Ophthalmology 121(1): 417-422.

Table 4a. Coefficients for conversion to core levels of visual impairment Conversion to blind (< 3/60) Intercept Coefficients from < 6/60 -1.01 .03 .91 .01 from â&#x2030;¤ 6/60 -1.21 .14 .81 .03

N 1024 76

Adjusted R-squared .90 .91

Conversion to MSVI (< 6/18 and â&#x2030;Ľ 3/60) Intercept Coefficients N from < 6/18 -.51 .01 .91 .004 1471 from < 6/12 -1.22 .05 .85 .02 108

Adjusted R-squared .96 .95

Table 4b. Model fit statistics Blind elpd loo p loo looic

Estimate -12262.8 265.6 24525.5

SE 120.2 14.6 240.3

MSVI elpd loo p loo looic

Estimate -15733.1 611.1 31466.3

SE 258.0 50.4 515.9

33

Table 5. Crude prevalence of vision impairment by sex, region, superregion in the year, 2015. 80% uncertainty interval is shown in parentheses.

Region

Superregion

Asia, Central Europe, Central Europe, Eastern

-

Central Europe, Eastern Europe, and Central Asia

Asia Pacific, High Income Australasia Europe, Western Latin America, Southern North America, High Income -

High-income

Caribbean Latin America, Andean Latin America, Central Latin America, Tropical -

Latin America and Caribbean

Males aged 50+ years Blind MSVI Mild VI 1.14 6.90 6.20 (0.37 (2.60 (1.89 2.11) 12.51) 12.09) 0.99 5.33 5.02 (0.26 (1.68 (1.27 1.96) 9.97) 10.06) 0.86 6.53 6.09 (0.27 (2.52 (1.83 1.63) 11.48) 11.66)

Females aged 50+ years Blind MSVI Mild VI 1.43 1.14 6.90 (0.46 (0.37 (2.60 2.67) 2.11) 12.51) 1.34 0.99 5.33 (0.35 (0.26 (1.68 2.78) 1.96) 9.97) 1.24 0.86 6.53 (0.39 (0.27 (2.52 2.37) 1.63) 11.48)

0.94 (0.28 1.81) 0.54 (0.28 0.85) 0.57 (0.24 1.02) 0.53 (0.28 0.85) 0.74 (0.32 1.27) 0.62 (0.27 1.08) 0.57 (0.27 0.95) 1.98 (0.69 3.59) 2.09 (0.71 3.86) 1.67 (0.61 2.95) 1.21 (0.42 2.19) 1.55 (0.55 2.77)

1.30 (0.39 2.53) 0.84 (0.44 1.31) 0.76 (0.31 1.35) 0.78 (0.41 1.23) 1.09 (0.48 1.87) 0.85 (0.36 1.48) 0.83 (0.40 1.36) 2.32 (0.79 4.25) 2.46 (0.84 4.58) 1.94 (0.70 3.43) 1.45 (0.50 2.63) 1.81 (0.63 3.26)

6.17 (2.25 11.10) 5.01 (2.57 7.94) 5.37 (2.36 9.25) 4.50 (2.23 7.36) 6.77 (3.22 11.31) 4.70 (2.01 7.87) 4.78 (2.27 7.84) 7.88 (3.31 13.51) 12.12 (5.73 20.02) 8.00 (3.45 13.50) 5.70 (2.12 10.14) 7.43 (3.10 12.73)

5.74 (1.65 11.17) 5.00 (1.82 8.98) 5.25 (1.72 9.87) 4.52 (1.57 8.55) 6.39 (2.31 11.93) 4.63 (1.53 8.86) 4.74 (1.64 8.90) 6.78 (2.31 12.87) 9.78 (3.72 17.60) 7.00 (2.41 13.04) 5.38 (1.64 10.39) 6.57 (2.21 12.36)

0.94 (0.28 1.81) 0.54 (0.28 0.85) 0.57 (0.24 1.02) 0.53 (0.28 0.85) 0.74 (0.32 1.27) 0.62 (0.27 1.08) 0.57 (0.27 0.95) 1.98 (0.69 3.59) 2.09 (0.71 3.86) 1.67 (0.61 2.95) 1.21 (0.42 2.19) 1.55 (0.55 2.77)

6.17 (2.25 11.10) 5.01 (2.57 7.94) 5.37 (2.36 9.25) 4.50 (2.23 7.36) 6.77 (3.22 11.31) 4.70 (2.01 7.87) 4.78 (2.27 7.84) 7.88 (3.31 13.51) 12.12 (5.73 20.02) 8.00 (3.45 13.50) 5.70 (2.12 10.14) 7.43 (3.10 12.73)

Presbyopes aged 50+ years

51.20 (21.65 80.77)

11.69 (3.32 23.86)

45.42 (5.19 90.62)

Males, all ages Blind MSVI Mild VI 0.23 1.58 1.50 (0.08 (0.57 (0.42 0.43) 2.89) 2.97) 0.36 2.03 1.95 (0.10 (0.63 (0.48 0.71) 3.80) 3.92) 0.29 2.31 2.20 (0.09 (0.88 (0.63 0.54) 4.07) 4.26)

Females, all ages Blind MSVI Mild VI 0.34 2.08 1.87 (0.11 (0.76 (0.54 0.63) 3.75) 3.68) 0.56 2.86 2.62 (0.15 (0.86 (0.66 1.16) 5.38) 5.19) 0.52 3.67 3.29 (0.16 (1.40 (1.02 0.99) 6.62) 6.18)

0.30 (0.09 0.57) 0.22 (0.12 0.35) 0.20 (0.08 0.35) 0.21 (0.11 0.33) 0.19 (0.08 0.33) 0.22 (0.09 0.38) 0.21 (0.10 0.35) 0.49 (0.17 0.89) 0.41 (0.14 0.77) 0.34 (0.12 0.60) 0.29 (0.10 0.52) 0.34 (0.12 0.61)

0.49 (0.15 0.96) 0.38 (0.20 0.60) 0.27 (0.11 0.49) 0.33 (0.18 0.53) 0.32 (0.14 0.56) 0.33 (0.14 0.57) 0.34 (0.16 0.55) 0.60 (0.20 1.10) 0.53 (0.18 0.98) 0.42 (0.15 0.75) 0.38 (0.13 0.69) 0.43 (0.15 0.78)

2.07 (0.74 3.74) 2.13 (1.09 3.39) 1.93 (0.84 3.33) 1.84 (0.91 3.02) 1.88 (0.88 3.16) 1.75 (0.74 2.93) 1.86 (0.88 3.07) 2.10 (0.86 3.64) 2.66 (1.21 4.48) 1.77 (0.74 3.01) 1.46 (0.53 2.61) 1.77 (0.72 3.06)

1.97 (0.54 3.88) 2.14 (0.77 3.87) 1.90 (0.61 3.61) 1.86 (0.64 3.54) 1.82 (0.63 3.44) 1.74 (0.56 3.35) 1.87 (0.63 3.53) 1.89 (0.60 3.66) 2.31 (0.80 4.32) 1.62 (0.52 3.09) 1.42 (0.41 2.77) 1.64 (0.51 3.14)

3.12 (1.12 5.69) 3.32 (1.73 5.20) 2.51 (1.12 4.27) 2.68 (1.35 4.34) 2.84 (1.38 4.71) 2.42 (1.06 4.04) 2.71 (1.31 4.41) 2.45 (0.96 4.28) 3.17 (1.43 5.33) 2.08 (0.85 3.57) 1.79 (0.64 3.18) 2.11 (0.83 3.65)

2.81 (0.82 5.39) 3.15 (1.20 5.53) 2.39 (0.79 4.42) 2.60 (0.94 4.82) 2.57 (0.96 4.74) 2.31 (0.79 4.36) 2.59 (0.93 4.77) 2.13 (0.67 4.10) 2.63 (0.92 4.86) 1.85 (0.59 3.49) 1.68 (0.49 3.30) 1.89 (0.59 3.60)

Presbyopes, all ages

44.75 (17.93 73.20)

9.98 (2.79 - 20.26)

38.75 (3.87 83.38)

North Africa/Middle East Asia, South

North Africa and Middle East South Asia

Asia, East Asia, Southeast Oceania

-

Southeast Asia, East Asia, and Oceania

Sub-Saharan Africa, Central Sub-Saharan Africa, East Sub-Saharan Africa, Southern Sub-Saharan Africa, West World

Sub-Saharan Africa -

3.01 (1.00 5.38) 3.20 (1.18 5.84) 1.23 (0.41 2.25) 2.11 (0.79 3.74) 2.26 (0.77 4.20)

14.45 (7.10 22.76) 14.99 (7.71 23.59) 10.07 (4.61 16.82) 11.78 (5.76 18.87) 9.30 (4.16 15.49)

10.79 (4.21 18.93) 11.32 (4.47 19.86) 8.69 (3.16 15.89) 9.64 (3.69 17.10) 8.09 (2.88 14.82)

3.73 (1.23 6.71) 3.74 (1.31 6.93) 1.54 (0.52 2.87) 2.66 (0.99 4.77) 2.75 (0.93 5.16)

3.01 (1.00 5.38) 17.09 (8.66 26.85) 11.88 (5.28 19.98) 13.49 (6.59 21.51) 10.62 (4.68 17.91)

14.45 (7.10 22.76) 12.22 (4.82 21.33) 9.68 (3.60 17.61) 10.42 (4.04 18.35) 8.82 (3.13 16.28)

44.60 (5.90 88.44)

1.43 (0.50 2.60) 1.99 (0.61 3.73) 3.49 (1.35 6.04) 2.85 (0.99 5.26) 3.55 (1.35 6.27) 3.28 (1.23 5.79) 1.71 (0.63 3.08)

10.46 (4.87 17.28) 11.58 (4.86 19.91) 11.42 (5.35 18.61) 7.79 (3.54 12.94) 12.96 (6.30 20.82) 11.70 (5.50 19.09) 9.72 (4.62 15.85)

8.91 (3.28 16.16) 9.51 (3.34 17.57) 9.10 (3.40 16.39) 6.70 (2.38 12.19) 10.22 (3.98 18.00) 9.37 (3.53 16.76) 8.11 (2.99 14.69)

1.82 (0.63 3.35) 2.47 (0.75 4.80) 3.82 (1.45 6.67) 3.49 (1.18 6.43) 3.99 (1.48 7.19) 3.69 (1.35 6.63) 2.05 (0.74 3.73)

12.28 (5.60 20.35) 13.79 (5.75 23.73) 12.53 (5.69 20.73) 9.22 (4.00 15.45) 14.21 (6.71 23.03) 12.90 (5.88 21.29) 11.22 (5.25 18.36)

9.86 (3.71 17.79) 10.67 (3.82 19.23) 9.71 (3.62 17.45) 7.61 (2.67 13.89) 10.81 (4.17 19.08) 9.98 (3.74 17.83) 8.96 (3.34 16.13)

41.91 (23.24 61.67)

64.84 (51.97 77.48)

59.83 (43.91 75.10) 40.30 (22.00 60.41)

0.53 (0.17 0.96) 0.63 (0.23 1.15) 0.37 (0.13 0.69) 0.46 (0.17 0.82) 0.35 (0.12 0.65)

2.90 (1.34 4.69) 3.31 (1.62 5.33) 3.32 (1.48 5.59) 2.89 (1.36 4.72) 1.57 (0.67 2.66)

2.43 (0.84 4.49) 2.79 (0.98 5.11) 2.99 (1.02 5.59) 2.57 (0.90 4.72) 1.48 (0.47 2.80)

0.70 (0.22 1.26) 0.77 (0.26 1.43) 0.49 (0.16 0.92) 0.63 (0.23 1.12) 0.45 (0.15 0.85)

3.57 (1.64 5.75) 3.95 (1.89 6.36) 4.09 (1.77 6.95) 3.51 (1.65 5.70) 1.93 (0.81 3.33)

2.82 (0.98 5.17) 3.19 (1.12 5.83) 3.50 (1.21 6.52) 2.94 (1.04 5.38) 1.74 (0.56 3.33)

36.97 (4.27 79.27)

0.40 (0.14 0.73) 0.23 (0.07 0.44) 0.40 (0.15 0.70) 0.42 (0.14 0.78) 0.44 (0.16 0.79) 0.40 (0.15 0.71) 0.43 (0.15 0.77)

3.18 (1.44 5.31) 1.59 (0.62 2.79) 1.51 (0.67 2.51) 1.29 (0.56 2.18) 1.86 (0.85 3.07) 1.65 (0.73 2.75) 2.64 (1.21 4.37)

2.86 (0.98 5.31) 1.47 (0.44 2.83) 1.35 (0.44 2.54) 1.20 (0.39 2.23) 1.67 (0.56 3.09) 1.48 (0.49 2.77) 2.35 (0.80 4.38)

0.53 (0.19 0.98) 0.31 (0.09 0.60) 0.48 (0.18 0.85) 0.65 (0.21 1.20) 0.53 (0.19 0.95) 0.49 (0.18 0.89) 0.55 (0.20 1.01)

3.89 (1.72 6.54) 1.98 (0.77 3.50) 1.80 (0.77 3.04) 1.85 (0.78 3.13) 2.16 (0.95 3.60) 1.97 (0.84 3.33) 3.27 (1.47 5.42)

3.31 (1.16 6.15) 1.74 (0.53 3.29) 1.56 (0.51 2.93) 1.62 (0.53 3.03) 1.87 (0.62 3.49) 1.71 (0.56 3.21) 2.79 (0.96 5.17)

33.87 (17.95 51.22)

53.23 (41.19 65.60)

47.26 (33.02 61.57) 34.64 (18.27 53.55)

Table 6. Global crude prevalence of visual impairment by age and sex, in the year 2015. Percentage prevalence is given with 80% uncertainty interval in parentheses.

Blind Age (years) 0 to 4 5 to 9 10 to 14 15 to 19 20 to 24 25 to 29 30 to 34 35 to 39 40 to 44 45 to 49 50 to 54 55 to 59 60 to 64

Males 0.03 (0.01 - 0.05) 0.04 (0.01 - 0.07) 0.04 (0.01 - 0.08) 0.05 (0.02 - 0.10) 0.06 (0.02 - 0.12) 0.07 (0.02 - 0.14) 0.09 (0.03 - 0.17) 0.11 (0.04 - 0.21) 0.15 (0.05 - 0.28) 0.26 (0.09 - 0.47) 0.42 (0.14 - 0.77) 0.72 (0.24 - 1.32) 1.16 (0.40 - 2.12)

Females 0.03 (0.01 - 0.06) 0.04 (0.01 - 0.07) 0.05 (0.02 - 0.09) 0.06 (0.02 - 0.11) 0.07 (0.02 - 0.12) 0.08 (0.03 - 0.15) 0.10 (0.03 - 0.18) 0.12 (0.04 - 0.23) 0.17 (0.05 - 0.31) 0.28 (0.09 - 0.53) 0.46 (0.15 - 0.86) 0.79 (0.26 - 1.47) 1.26 (0.42 - 2.35)

65 to 69

1.94 (0.68 - 3.52)

2.10 (0.71 - 3.89)

70 to 74

3.03 (1.09 - 5.48)

3.24 (1.13 - 5.95)

75 to 79

4.27 (1.58 - 7.67)

4.47 (1.61 - 8.15)

80 to 84

5.95 (2.30 - 10.55)

6.08 (2.29 - 10.90)

85 to 89

7.93 (3.23 - 13.81) 11.28 (4.96 - 19.03)

7.74 (3.09 - 13.59) 10.34 (4.52 - 17.50)

90 plus

Moderate and Severe Vision Impairment Males 0.20 (0.08 - 0.34) 0.25 (0.10 - 0.44) 0.32 (0.13 - 0.56) 0.41 (0.16 - 0.72) 0.52 (0.21 - 0.90) 0.65 (0.26 - 1.14) 0.83 (0.33 - 1.45) 1.09 (0.44 - 1.90) 1.50 (0.60 - 2.62) 2.39 (0.97 - 4.15) 3.62 (1.49 - 6.24) 5.70 (2.43 - 9.76) 8.41 (3.71 - 14.23) 12.46 (5.81 - 20.55) 16.67 (8.18 - 26.79) 20.17 (10.32 - 31.74) 23.96 (12.86 - 36.71) 27.53 (15.40 - 41.15) 32.83 (19.45 - 47.43)

Females 0.20 (0.08 - 0.36) 0.26 (0.10 - 0.46) 0.34 (0.13 - 0.60) 0.43 (0.16 - 0.76) 0.54 (0.20 - 0.95) 0.71 (0.27 - 1.25) 0.90 (0.34 - 1.59) 1.20 (0.46 - 2.12) 1.65 (0.63 - 2.90) 2.64 (1.03 - 4.65) 3.97 (1.57 - 6.93) 6.24 (2.55 - 10.81) 9.13 (3.88 - 15.61) 13.47 (6.09 - 22.42) 17.74 (8.48 - 28.72) 21.18 (10.53 - 33.58) 24.84 (12.98 - 38.37) 27.84 (15.14 - 42.07) 32.16 (18.51 - 47.05)

Mild Vision Impairment Males 0.21 (0.05 - 0.42) 0.27 (0.07 - 0.55) 0.35 (0.09 - 0.71) 0.45 (0.11 - 0.90) 0.57 (0.14 - 1.13) 0.72 (0.18 - 1.44) 0.92 (0.24 - 1.84) 1.20 (0.31 - 2.41) 1.64 (0.44 - 3.29) 2.58 (0.71 - 5.13) 3.80 (1.10 - 7.53) 5.73 (1.77 - 11.16) 7.98 (2.66 - 15.14) 10.75 (4.03 - 19.34) 13.00 (5.37 - 22.29) 14.32 (6.29 - 23.77) 15.19 (6.85 - 24.70) 15.51 (6.90 - 25.19) 15.44 (6.44 - 25.23)

Females 0.22 (0.05 - 0.45) 0.29 (0.07 - 0.58) 0.37 (0.09 - 0.75) 0.47 (0.12 - 0.95) 0.59 (0.15 - 1.19) 0.78 (0.19 - 1.57) 0.99 (0.25 - 2.00) 1.32 (0.33 - 2.66) 1.79 (0.46 - 3.62) 2.83 (0.76 - 5.69) 4.13 (1.17 - 8.24) 6.18 (1.89 - 12.12) 8.49 (2.82 - 16.14) 11.35 (4.27 - 20.28) 13.47 (5.57 - 22.95) 14.67 (6.41 - 24.35) 15.46 (6.92 - 25.19) 15.80 (6.88 - 25.78) 16.11 (7.07 - 26.01)

Table 7. Age-standardised prevalence of vision impairment by sex, region, superregion in the year, 2015. 80% uncertainty interval is shown in parentheses.

Males aged 50+ years Region

Blind

MSVI

Mild VI

Blind

MSVI

Mild VI

Asia, Central

1.45 (0.48 - 2.69)

8.27 (3.19 - 14.87)

7.18 (2.28 - 13.81)

1.48 (0.48 - 2.78)

8.47 (3.19 - 15.17)

7.29 (2.27 - 14.07)

Europe, Central

0.93 (0.25 - 1.85)

5.06 (1.59 - 9.46)

4.77 (1.20 - 9.58)

0.98 (0.26 - 2.04)

5.29 (1.58 - 10.02)

4.94 (1.22 - 9.92)

Europe, Eastern

0.96 (0.31 - 1.81)

7.01 (2.73 - 12.27)

6.44 (1.97 - 12.25)

0.98 (0.30 - 1.87)

7.17 (2.72 - 13.00)

6.53 (2.00 - 12.36)

1.00 (0.30 - 1.92)

6.41 (2.35 - 11.51)

5.91 (1.72 - 11.47)

1.03 (0.30 - 2.01)

6.70 (2.39 - 12.27)

6.11 (1.78 - 11.80)

Asia Pacific, High Income

0.42 (0.22 - 0.66)

4.09 (2.08 - 6.52)

4.15 (1.47 - 7.51)

0.48 (0.25 - 0.76)

4.88 (2.48 - 7.74)

Australasia

0.49 (0.20 - 0.87)

4.79 (2.08 - 8.28)

4.75 (1.52 - 9.00)

0.54 (0.22 - 0.97)

Europe, Western

0.42 (0.22 - 0.67)

3.78 (1.86 - 6.21)

3.86 (1.31 - 7.36)

Latin America, Southern

0.71 (0.31 - 1.22)

6.58 (3.12 - 11.01)

North America, High Income

0.56 (0.24 - 0.98)

4.40 (1.87 - 7.38)

-

Superregion

Females aged 50+ years

Central Europe, Eastern Europe, and Central Asia

Presbyopes aged 50+ years

Males, all ages Mild Blind MSVI VI 2.00 0.36 2.20 (0.59 (0.12 - (0.82 - - 0.66) 3.99) 3.90) 1.29 0.23 1.33 (0.31 (0.06 - (0.41 - - 0.45) 2.49) 2.59) 1.75 0.23 1.84 (0.51 (0.07 - (0.70 - - 0.44) 3.25) 3.38) 0.25 (0.07 - 0.47)

1.71 (0.61 - 3.08)

4.83 (1.75 - 8.64)

0.10 (0.05 - 0.16)

1.06 (0.53 - 1.70)

5.42 (2.38 - 9.27)

5.28 (1.71 - 9.88)

0.12 (0.05 - 0.21)

1.25 (0.54 - 2.17)

0.48 (0.25 - 0.76)

4.37 (2.15 - 7.14)

4.39 (1.52 - 8.30)

0.10 (0.05 - 0.16)

0.98 (0.48 - 1.62)

6.25 (2.25 - 11.70)

0.78 (0.34 - 1.34)

7.35 (3.52 - 12.28)

6.85 (2.51 - 12.73)

0.17 (0.07 - 0.30)

1.71 (0.80 - 2.89)

4.37 (1.43 - 8.42)

0.63 (0.27 - 1.09)

5.00 (2.17 - 8.39)

4.90 (1.63 - 9.34)

0.14 (0.06 - 0.24)

1.16 (0.48 - 1.95)

51.88 (22.29 - 81.26)

1.63 (0.44 - 3.19) 1.09 (0.37 - 1.99) 1.26 (0.39 - 2.41) 1.01 (0.33 - 1.95) 1.67 (0.57 - 3.17) 1.17 (0.37 - 2.27)

Females, all ages Blind

MSVI

Mild VI

0.36 (0.12 - 0.68)

2.25 (0.82 - 4.05)

2.02 (0.59 - 3.97)

0.24 (0.06 - 0.49)

1.38 (0.40 - 2.61)

1.32 (0.31 - 2.66)

0.24 (0.07 - 0.45)

1.88 (0.69 - 3.43)

1.76 (0.51 - 3.39)

0.25 (0.07 - 0.49)

1.77 (0.62 - 3.26)

1.67 (0.46 - 3.26)

0.12 (0.06 - 0.18)

1.26 (0.63 - 2.01)

1.26 (0.44 - 2.28)

0.13 (0.05 - 0.24)

1.41 (0.61 - 2.43)

1.40 (0.44 - 2.66)

0.12 (0.06 - 0.18)

1.13 (0.55 - 1.86)

1.15 (0.39 - 2.20)

0.19 (0.08 - 0.33)

1.91 (0.90 - 3.22)

1.83 (0.64 - 3.47)

0.15 (0.06 - 0.27)

1.31 (0.56 - 2.21)

1.31 (0.42 - 2.53)

Presbyopes, all ages

44.16 (17.79 - 72.25)

0.47 (0.23 - 0.78)

4.16 (1.96 - 6.86)

4.19 (1.42 - 7.93)

0.54 (0.26 - 0.88)

4.82 (2.29 - 7.91)

4.77 (1.65 - 8.92)

0.12 (0.06 - 0.19)

1.09 (0.51 - 1.81)

Caribbean

1.96 (0.68 - 3.56)

7.92 (3.32 - 13.60)

6.87 (2.33 - 13.05)

2.07 (0.69 - 3.80)

8.25 (3.29 - 14.37)

7.05 (2.33 - 13.44)

0.49 (0.17 - 0.89)

2.12 (0.86 - 3.68)

Latin America, Andean

2.15 (0.73 - 3.97)

12.39 (5.87 - 20.46)

9.96 (3.80 - 17.88)

2.28 (0.77 - 4.25)

13.05 (6.04 - 21.64)

10.28 (3.87 - 18.42)

0.52 (0.18 - 0.97)

3.30 (1.51 - 5.52)

Latin America, Central

1.79 (0.65 - 3.15)

8.47 (3.66 - 14.26)

7.35 (2.55 - 13.63)

1.85 (0.66 - 3.29)

8.67 (3.61 - 14.82)

7.48 (2.55 - 13.85)

0.44 (0.16 - 0.77)

2.22 (0.94 - 3.76)

Latin America, Tropical

1.40 (0.49 - 2.52)

6.30 (2.38 - 11.16)

5.83 (1.82 - 11.17)

1.42 (0.49 - 2.58)

6.35 (2.29 - 11.26)

5.85 (1.78 - 11.37)

0.34 (0.12 - 0.61)

1.64 (0.61 - 2.92)

-

Latin America and Caribbean

1.69 (0.60 - 3.02)

7.93 (3.34 - 13.55)

6.93 (2.36 - 12.96)

1.73 (0.60 - 3.12)

8.06 (3.25 - 13.89)

7.01 (2.33 - 13.16)

45.24 (5.14 - 90.51)

0.41 (0.15 - 0.74)

2.09 (0.86 - 3.59)

North Africa/Middle East

North Africa and Middle East

3.69 (1.25 - 6.55)

16.43 (8.30 - 25.53)

11.54 (4.61 - 19.95)

4.07 (1.35 - 7.30)

17.99 (8.92 - 28.05)

12.19 (4.85 - 21.05)

44.06 (5.74 - 87.98)

0.90 (0.30 - 1.61)

4.38 (2.12 - 6.95)

3.83 (1.43 - 6.95)

16.72 (8.82 - 25.99)

11.92 (4.81 - 20.64)

4.18 (1.48 - 7.71)

18.26 (9.40 - 28.43)

12.56 (5.01 - 21.75)

63.83 (50.90 - 76.55)

0.94 (0.35 - 1.72)

4.53 (2.29 - 7.18)

South Asia

Asia, East

1.43 (0.49 - 2.62)

10.98 (5.12 - 18.19)

9.18 (3.44 - 16.56)

1.61 (0.54 - 3.00)

12.22 (5.46 - 20.48)

9.85 (3.69 - 17.83)

0.35 (0.12 - 0.64)

2.90 (1.31 - 4.86)

Asia, Southeast

2.68 (1.02 - 4.73)

13.72 (6.88 - 21.69)

10.61 (4.23 - 18.47)

2.89 (1.07 - 5.17)

14.34 (7.05 - 22.77)

10.88 (4.29 - 19.02)

0.66 (0.25 - 1.17)

3.70 (1.79 - 5.95)

Oceania

3.23 (1.14 - 5.95)

11.81 (5.53 - 19.28)

9.36 (3.52 - 16.70)

3.43 (1.19 - 6.37)

12.25 (5.55 - 20.38)

9.58 (3.51 - 17.39)

0.80 (0.28 - 1.47)

3.12 (1.41 - 5.15)

-

Asia, South

High-income

12.24 (3.56 - 24.83)

1.11 (0.36 - 2.12) 1.93 (0.61 - 3.73) 2.82 (1.00 - 5.22) 2.00 (0.66 - 3.79) 1.56 (0.47 - 3.03) 1.90 (0.61 - 3.61) 3.38 (1.23 - 6.08) 3.56 (1.31 - 6.40) 2.56 (0.89 - 4.73) 3.08 (1.13 - 5.56) 2.63 (0.92 - 4.82)

0.13 (0.06 - 0.22)

1.26 (0.59 - 2.07)

1.26 (0.42 - 2.39)

0.51 (0.17 - 0.94)

2.21 (0.85 - 3.89)

1.98 (0.61 - 3.84)

0.55 (0.19 - 1.04)

3.46 (1.55 - 5.83)

2.91 (1.01 - 5.38)

0.45 (0.16 - 0.80)

2.27 (0.92 - 3.91)

2.04 (0.65 - 3.84)

0.35 (0.12 - 0.63)

1.65 (0.58 - 2.94)

1.56 (0.45 - 3.06)

0.42 (0.15 - 0.76)

2.11 (0.83 - 3.68)

1.91 (0.60 - 3.66)

39.44 (3.99 - 84.20)

1.00 (0.33 - 1.80)

4.84 (2.29 - 7.71)

3.64 (1.31 - 6.57)

38.17 (4.49 - 80.87)

1.03 (0.36 - 1.91)

4.98 (2.45 - 7.92)

3.81 (1.38 - 6.89)

54.40 (42.20 - 66.86)

0.39 (0.13 - 0.73)

3.20 (1.39 - 5.45)

2.74 (0.95 - 5.10)

0.71 (0.26 - 1.27)

3.85 (1.83 - 6.22)

3.16 (1.14 - 5.72)

0.85 (0.29 - 1.58)

3.25 (1.43 - 5.49)

2.72 (0.93 - 5.07)

9.79 (2.76 - 19.80)

Southeast Asia, East Asia, and Oceania

1.70 (0.60 - 3.07)

11.57 (5.50 - 18.95)

9.51 (3.61 - 17.00)

1.92 (0.67 - 3.53)

12.73 (5.84 - 21.04)

10.11 (3.84 - 18.12)

Sub-Saharan Africa, Central

2.62 (0.83 - 4.87)

13.58 (5.94 - 22.93)

10.38 (3.81 - 18.76)

2.94 (0.91 - 5.69)

15.18 (6.53 - 25.78)

Sub-Saharan Africa, East

4.17 (1.66 - 7.15)

12.77 (6.14 - 20.58)

9.62 (3.67 - 17.15)

4.36 (1.68 - 7.54)

Sub-Saharan Africa, Southern

3.57 (1.25 - 6.54)

9.23 (4.27 - 15.23)

7.62 (2.77 - 13.73)

Sub-Saharan Africa, West

4.91 (1.96 - 8.50)

15.59 (7.94 - 24.47)

SubSaharan Africa

4.19 (1.62 - 7.32)

-

1.82 (0.67 - 3.28)

-

-

World

0.42 (0.15 - 0.76)

3.09 (1.42 - 5.13)

11.15 (4.08 - 19.87)

0.64 (0.20 - 1.20)

3.65 (1.53 - 6.25)

13.54 (6.28 - 22.18)

10.02 (3.79 - 17.88)

1.02 (0.40 - 1.76)

3.41 (1.58 - 5.55)

3.62 (1.23 - 6.65)

9.46 (4.12 - 15.81)

7.74 (2.72 - 14.09)

0.87 (0.30 - 1.61)

2.42 (1.09 - 4.03)

11.01 (4.40 - 19.08)

5.18 (2.01 - 9.17)

16.42 (8.08 - 26.07)

11.35 (4.45 - 19.79)

1.21 (0.47 - 2.10)

4.20 (2.05 - 6.71)

13.59 (6.60 - 21.84)

10.11 (3.92 - 17.82)

4.36 (1.63 - 7.76)

14.20 (6.63 - 23.16)

10.40 (3.96 - 18.41)

58.49 (42.59 - 73.84)

1.03 (0.39 - 1.81)

3.64 (1.71 - 5.94)

10.12 (4.85 - 16.45)

8.33 (3.10 - 15.02)

1.91 (0.68 - 3.49)

10.79 (5.00 - 17.74)

8.77 (3.23 - 15.84)

40.76 (22.32 - 60.98)

0.46 (0.17 - 0.84)

2.79 (1.29 - 4.61)

41.32 (22.80 - 60.98)

2.69 (0.95 - 4.95) 3.02 (1.01 - 5.63) 2.77 (0.98 - 5.06) 2.10 (0.72 - 3.85) 3.26 (1.20 - 5.84) 2.94 (1.05 - 5.34) 2.46 (0.84 - 4.55)

0.47 (0.16 - 0.86)

3.37 (1.50 - 5.65)

2.85 (1.00 - 5.28)

0.72 (0.22 - 1.40)

4.09 (1.68 - 7.07)

3.27 (1.08 - 6.04)

1.07 (0.41 - 1.87)

3.63 (1.62 - 6.03)

2.91 (1.01 - 5.34)

0.89 (0.30 - 1.64)

2.47 (1.05 - 4.18)

2.13 (0.71 - 3.96)

1.28 (0.49 - 2.28)

4.45 (2.10 - 7.22)

3.41 (1.22 - 6.18)

1.08 (0.40 - 1.93)

3.84 (1.72 - 6.37)

3.06 (1.07 - 5.61)

49.37 (34.75 - 63.96)

0.49 (0.17 - 0.90)

2.99 (1.33 - 4.99)

2.60 (0.88 - 4.85)

35.41 (18.77 - 54.62)

34.02 (18.01 - 51.49)

Table 9. PRISMA 2009 Checklist Section/topic

#

Checklist item

Reported on page #

1

Identify the report as a systematic review, meta-analysis, or both.

4, 5-8

TITLE Title

The report is identified as a systematic review in Abstract and Methods section.

ABSTRACT Structured summary

2

Provide a structured summary including, as applicable: background; objectives; data sources; study eligibility criteria, participants, and interventions; study appraisal and synthesis methods; results; limitations; conclusions and implications of key findings; systematic review registration number.

4

This summary is given in the abstract.

INTRODUCTION Rationale

3

Describe the rationale for the review in the context of what is already known.

5

The rationale is clearly stated in the Introduction section.

Objectives

4

Provide an explicit statement of questions being addressed with reference to participants, interventions, comparisons, outcomes, and study design (PICOS).

5

The rationale is clearly stated in the Introduction section.

METHODS Protocol and registration

5

Indicate if a review protocol exists, if and where it can be accessed (e.g., Web address), and, if available, provide registration information including registration number.

The systematic review strategy was published previously and the reference to this is given [reference 8]. The full search strategy is given in Text 2 of the Appendix

Eligibility criteria

6

Specify study characteristics (e.g., PICOS, length of follow-up) and report characteristics (e.g., years considered, language, publication status) used as criteria for eligibility, giving rationale.

7&8& Appendix Text 2 Appendix Text 2

The eligibility criteria are given in Text 2 of the Appendix, section 2.1. ‘Developing the Search Strategy’ Information sources

7

Describe all information sources (e.g., databases with dates of coverage, contact with study authors to identify additional studies) in the search and date last searched.

Appendix Text 2

The information sources are given in Text 2 of the Appendix, section 2.1. ‘Developing the Search Strategy’ and Section 2.2 ‘Final Search Strategies’.

Search

8

Present full electronic search strategy for at least one database, including any limits used, such that it could be repeated.

Appendix Text 2

This is given in Text 2 of the Appendix Section 2.2 ‘Final Search Strategies’.

Study selection

9

State the process for selecting studies (i.e., screening, eligibility, included in systematic review, and, if applicable, included in the meta-analysis).

The study selection for eligibility and screening is given in the main manuscript under Methods.

7

Table 9. PRISMA 2009 Checklist Data collection process

10

Describe method of data extraction from reports (e.g., piloted forms, independently, in duplicate) and any processes for obtaining and confirming data from investigators.

7

This is stated in the Methods section Data items

11

List and define all variables for which data were sought (e.g., PICOS, funding sources) and any assumptions and simplifications made.

7&8

This is stated in the Methods section Risk of bias in individual studies

12

Describe methods used for assessing risk of bias of individual studies (including specification of whether this was done at the study or outcome level), and how this information is to be used in any data synthesis.

The principal risk of bias with data sources resided with data sources that were not population-based, the visual acuity measurement methods were unclear or where the visual acuity cut-offs for vision loss were not compatible with those of this study. These were minimised by exclusion of full-text articles as shown in the PRISMA flowchart (Figure 9 Appendix) and the Methods section that explains the review by the expert panel.

Summary measures

13

State the principal summary measures (e.g., risk ratio, difference in means).

7& Appendix Fig 9

7&8

We estimated trends in causes of vision impairment, including analysis of uncertainties, by age, sex, and geographical region and fractions of blindness and visual impairment due to glaucoma. This is detailed in the Methods section Synthesis of results

14

Describe the methods of handling data and combining results of studies, if done, including measures of consistency 2 (e.g., I ) for each meta-analysis.

8-10

These are explained in the final sections of the Methods section.

Page 1 of 2

Section/topic Risk of bias across studies

# 15

Checklist item Specify any assessment of risk of bias that may affect the cumulative evidence (e.g., publication bias, selective reporting within studies).

Reported on page # 21 & 22

These are described under â&#x20AC;&#x2DC;limitations of the studyâ&#x20AC;&#x2122; in the Discussion section.

Additional analyses

16

Describe methods of additional analyses (e.g., sensitivity or subgroup analyses, meta-regression), if done, indicating which were pre-specified.

N/A

These were not performed.

RESULTS Study selection

17

Study characteristics

18

Give numbers of studies screened, assessed for eligibility, and included in the review, with reasons for exclusions at each stage, ideally with a flow diagram.

Appendix Fig 9

This is given as Appendix Fig 9 using a PRISMA flowchart For each study, present characteristics for which data were extracted (e.g., study size, PICOS, follow-up period) and provide the citations.

The citations are available in Table 2 of the Appendix

Appendix Table 2

Table 9. PRISMA 2009 Checklist Risk of bias within studies

Results of individual studies

19

20

Present data on risk of bias of each study and, if available, any outcome level assessment (see item 12).

We were unable to comment on this beyond the decision to exclude studies that carried a significant risk of bias as detailed in Point 12 of the checklist.

7 & Appendix Fig 9

For all outcomes considered (benefits or harms), present, for each study: (a) simple summary data for each intervention group (b) effect estimates and confidence intervals, ideally with a forest plot.

Main text & appendix

In terms of prevalence of vision impairment and blindness, the tables in both the manuscript and also the Appendix contain uncertainty intervals around all of the estimates Synthesis of results

21

Present results of each meta-analysis done, including confidence intervals and measures of consistency.

14-17

These results are reported with 80% Uncertainty Intervals in the results section and Tables.

Risk of bias across studies

22

Present results of any assessment of risk of bias across studies (see Item 15).

Appendix

The statistical model investigated the risk of bias across studies and an account of this can be found in the Appendix Additional analysis

23

Give results of additional analyses, if done (e.g., sensitivity or subgroup analyses, meta-regression [see Item 16]).

N/A

Not applicable.

DISCUSSION Summary of evidence

24

Summarize the main findings including the strength of evidence for each main outcome; consider their relevance to key groups (e.g., healthcare providers, users, and policy makers).

19-23

This is summarised in the discussions section.

Limitations

25

Discuss limitations at study and outcome level (e.g., risk of bias), and at review-level (e.g., incomplete retrieval of identified research, reporting bias).

19-23

The limitations are discussed in the discussion section.

Conclusions

26

Provide a general interpretation of the results in the context of other evidence, and implications for future research.

19-23

Please see the discussion and conclusions section.

FUNDING Funding

27

Describe sources of funding for the systematic review and other support (e.g., supply of data); role of funders for the systematic review.

4

These are given in the abstract section of the manuscript From: Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement. PLoS Med 6(7): e1000097. doi:10.1371/journal.pmed1000097

For more information, visit: www.prisma-statement.org.

Page 2 of 2

(Intercept)

presenting

−4.5 −5.0

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−5.5

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−6.5

0.09 0

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educ

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healthsys

−0.05

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age1

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is_ruralTRUE

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0.40

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0.35

−0.5 0.30

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Figure 1: Traceplots for important parameters in the blindness model showing 2,000 posterior draws total across 4 parallel chains.

43

1.0

Prevalence of visual acuity <3/60

0.9 0.8 0.7 ●

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0.3 0.2 0.1 0.0

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● ● ● ● ● ● ● ● ● ● ● ● ●● ● ●● ● ●● ● ● ● ● ● ●● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ●● ● ● ● ●● ●● ● ● ● ●● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ●●●●● ● ● ● ● ●● ●● ●● ●● ●● ●● ●● ●● ● ● ● ●●● ● ● ● ● ● ● ●● ●● ●●●● ● ● ● ● ● ● ● ●● ●● ● ● ●● ● ● ● ●● ● ● ● ● ●●●● ● ● ● ● ● ●● ● ●●●●● ● ●● ●● ● ● ●● ●● ●● ●● ● ● ● ●● ● ● ●●●● ● ● ●●●●●● ● ● ●● ● ●●●● ●● ●● ● ● ●● ● ● ●● ●● ● ●● ● ●●● ●●● ●● ● ● ● ●● ●● ●● ●● ● ●● ● ●● ● ● ●● ● ● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ●●●● ● ●● ● ● ●● ● ● ● ●● ● ●● ● ● ● ● ● ● ●● ● ●● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ●● ● ● ● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ●● ● ● ●● ● ● ● ●● ● ●● ● ● ● ● ●● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ●● ● ● ● ● ● ● ● ● ●● ● ● ● ●● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ●● ● ● ● ● ●● ● ● ● ● ● ●● ● ● ● ● ● ● ● ●

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0.3 0.4 0.5 0.6 0.7 Prevalence of visual acuity <6/60 ●

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Survey data

Figure 2: Conversion from visual acuity < 6/60 to blind (< 3/60)

44

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Prevalence of visual acuity <3/60

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0.0

●

● ● ●

0.1 0.2 Prevalence of visual acuity ≤ 6/60 variable

●

Predicted value

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Survey data

Figure 3: Conversion from visual acuity ≤ 6/60 to blind (< 3/60)

45

0.3

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Prevalence of visual acuity <6/18 & ≥ 3/60

0.9 0.8 ● ●

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Figure 4: Conversion from visual acuity < 6/18 to MSVI (< 6/18 and ≥ 3/60

46

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● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ●● ● ● ● ●● ● ● ●● ● ● ●● ● ● ● ● ● ●● ● ● ● ● ● ●● ● ● ● ● ● ● ● ●● ● ● ● ● ●●● ●● ● ●●● ●● ● ● ●● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ●● ● ● ● ●●● ●● ●● ●● ●●● ●● ●● ●● ● ● ●● ● ●● ● ●●● ● ● ● ●●●● ● ● ● ● ● ● ● ● ● ●● ●● ● ● ● ●● ●● ● ● ● ●● ●●● ●● ● ●● ●● ●●● ● ● ● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●● ● ● ● ● ● ●● ●● ● ● ● ● ● ● ● ●● ● ● ●● ●●●● ●●● ●●● ● ● ● ● ●● ●● ● ●● ●● ● ●● ● ●● ●● ●● ● ● ● ● ● ●● ●● ● ● ● ● ● ● ● ● ●●●● ●●●●●●● ● ●● ● ● ● ● ● ● ● ● ●● ●●●●●● ● ● ● ● ● ● ● ● ●●● ● ●● ●●● ● ● ● ● ● ● ● ● ●●●●●● ● ● ● ●●●● ● ● ● ●● ● ● ● ● ● ● ● ● ●●● ●●● ●● ● ● ● ● ●● ● ● ●● ●● ● ●● ● ● ●● ●●● ●● ● ●● ● ● ● ●● ● ● ●● ● ●● ● ●● ● ● ●●● ●●● ●●● ●● ● ● ● ● ● ● ● ● ● ● ●●●● ● ●● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ●● ●●●●● ●● ● ● ● ●● ●● ●● ●●● ●●● ● ●● ● ● ● ● ● ● ● ● ● ● ●● ●●●● ●●● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ●●● ●● ● ● ● ● ● ●●● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ●● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ●

0.0

●

●

●

●

0.9

1.0

1.0

Prevalence of visual acuity <6/18 & ≥ 3/60

0.9 0.8 0.7 0.6

●

●

0.5

● ● ● ●

0.4

●

●

● ● ● ● ●

● ●

0.3

● ●

●

● ● ●

0.2

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● ●

0.1 0.0

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● ●

●

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●

●

●

●

●

●● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ●● ● ● ● ●● ● ● ●● ● ● ● ● ●● ● ● ● ● ● ●●●● ● ● ● ●● ●● ● ●●● ● ● ● ●

0.0

0.1

0.2

0.3 0.4 0.5 0.6 0.7 Prevalence of visual acuity <6/12 variable

●

Predicted value

●

0.8

Survey data

Figure 5: Conversion from visual acuity < 6/12 to MSVI (< 6/18 and ≥ 3/60

47

0.9

1.0

Prevalence of visual acuity <6/18 and ≥ 6/60

0.4

0.3

0.2

0.1

0.0

● ●●● ● ● ●● ●●● ● ● ●● ● ● ● ● ●● ●● ●●● ● ●● ● ● ●●● ● ● ● ●● ● ● ●●● ● ● ●● ● ●● ● ● ● ●●● ● ● ● ●● ● ● ● ● ● ● ● ● ●●● ● ● ● ●●●●● ● ● ● ● ● ●● ●● ● ● ●● ● ● ●● ● ●●● ● ● ● ● ● ●●●●●● ● ● ●● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ●●● ●● ●● ● ● ● ● ● ● ●● ● ●● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 0.0

0.2

0.4

●

0.6

0.8

Prevalence of visual acuity <6/18 and ≥ 6/60

Prevalence of visual acuity <6/18 and ≥ 3/60 0.4

0.3

0.2

0.1

0.0

● ● ●● ●● ● ● ●● ●●●● ● ● ● ● ● ● ●●●●● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ●●● ●●● ●● ●● ● ● ● ● ● ●● ●● ● ●● ● ●● ●● ● ●● ●● ● ● ● ● ●● ● ● ●●● ●● ● ● ● ● ●● ● ● ●●●● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ●●●● ● ● ● ● ● ● ● ●● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●●●● ● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ●●●● ● ● ●● ● ● ● ● ● 0.0

0.2

0.4

● ●

●

0.6

Prevalence of visual acuity <3/60 Survey data ● Predicted value

Figure 6: Prediction of severe vision impairment prevalence from MSVI and blind prevalence

48

Prevalence of visual acuity <6/18 and ≥ 6/60

0.6

0.4

0.2

0.0

● ● ●● ● ● ●● ● ●●● ● ●● ● ● ● ● ● ● ● ● ● ● ●● ●●●●● ● ●● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ●● ●● ●● ● ●● ●● ●●● ●● ● ● ● ● ● ● ● ● ●● ● ● ●● ● ● ● ● ●● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●● ● ● ● ● ●● ● ● ● ● ● ● ●● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● 0.0

0.2

0.4

0.6

0.8

Prevalence of visual acuity <6/18 and ≥ 6/60

Prevalence of visual acuity <6/18 and ≥ 3/60 0.6

0.4

0.2

0.0

● ● ● ● ●● ● ●● ● ● ● ●● ● ●● ● ● ● ● ●●● ● ●● ● ● ●●● ● ●●● ● ● ● ● ●● ● ●● ●● ● ● ● ● ● ●● ●●●● ● ● ●●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ●●● ● ● ● ● ● ● ●● ●●● ● ●● ● ● ● ●● ● ● ● ● ● ● ●● ● ● ● ●●●● ●● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ●● ● ● ● ●● ● ●● ●● ● ●● ●● ● ● ●● ●● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ●● ●● ● ● ●● ●● ● ● ●● ● ● ● ● ● ● ● ●● ● ● ●● ● ●●●● ● ●● ● ●● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ●● ● ● ● ● ●●● ● ● ● ● ●● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●● ● ● ●●● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●●● ●● ● 0.0

0.2

0.4

● ●

●

0.6

Prevalence of visual acuity <3/60 Survey data ● Predicted value

Figure 7: Prediction of moderate vision impairment prevalence from MSVI and blind prevalence

49

Prevalence of visual acuity <6/12 & ≥ 6/18

0.3

0.2

0.1

0.0

● ● ●● ● ●● ● ● ● ●● ● ● ● ● ● ●● ● ● ● ● ● ● ● ● ● ●

● ● ●● ●● ● ●● ● ● ● ●● ●● ● ● ● ● ● ●

0.0

0.2

●

●

● ●

●

●

0.4

0.6

Prevalence of visual acuity <6/12 & ≥ 6/18

Prevalence of visual acuity <6/18 & ≥ 3/60 0.3

● 0.2

0.1

0.0

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Prevalence of visual acuity <3/60 Survey data ● Predicted value

Figure 8: Prediction of mild vision impairment prevalence from MSVI and blind prevalence

50

Identification

Figure 9. PRISMA Flow Diagram* detailing the stages of the † systematic review extension to include more recently published studies up to July 2014 (Appendix Text 2) and numbers of records included or excluded.

Records identified through database searching (n = 3,878)

Eligibility

Screening

Records after duplicates removed (n = 1,903)

Records screened (n = 1,903)

Records excluded (n = 1,683)

Full-text articles assessed for eligibility (n = 220)

Full-text articles excluded (n = 1139) §

Included

Studies included in qualitative synthesis (n = 61)

Studies included in quantitative synthesis (meta-analysis) (n = 61) *Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement. PLoS Med 6(7): e1000097. doi:10.1371/journal.pmed1000097 § Reasons for exclusion included: i. Surveys that were not performed as random sample cross-sectional surveys of representative populations (eg. hospital or clinic case series, blindness registries and interview studies with self-reported vision status). ii. Lack of clearly stated definitions of VI or blindness using thresholds of visual acuity, in the better eye that matched or could be later modeled to match the definitions used by this study. iii. Failure to state best-corrected and/or presenting visual acuity. iv. Failure to clearly state the procedures used for measurement of visual acuity. Studies that were not excluded were deemed high quality and therefore were included in the qualitative synthesis. † 8 This was an extension of the systematic review published previously