Evaluation of Abstracts Dr Lukman Thalib Faculty of Medicine Kuwait University
First Impression! • It’s usually the first thing that readers. • It can be used to accept or reject.
Abstracting • Only Abstracts may be published. • Abstracts are published on multiple computerised databases and conference proceedings.
What should be in an Abstract?
Abstract is an overview • It is a summary of the essence and most important aspects of your study. • Main points and results. • Complete and compelling information. • Not a detective story which builds suspense as the reader hunts for clues, and should not be vague in its content.
Why, How and What? • Why the work was done? • How the work was done? • What was found?
Questions that may be asked? – Why did I do my research? What was interesting/useful about my research? – What was my methodology? – What were my main findings/results? – What were my principal conclusions? – What do my findings mean or implications?
Why did I do my research? What was interesting/useful about my research? • Motivation: Why do we care about the problem and the results? • Problem statement: What problem are you trying to solve? What is the scope of your work (a generalized approach, or for a specific situation)? Be careful not to use too much jargon. If possible capture the motivation and problem statement in a single sentence for smaller abstract.
What was my methodology? • How did you go about solving or making progress on the problem? • Study design, sample size, major analytical method, primary end point, outcome variables and measurement issues all captured in nutshell.
Results What's the answer? Put the result there, in numbers. Avoid vague, hand-waving results such as "very", "small", or "significant."
Conclusions and implications • What are the implications of your answer? Is it going to change the world (unlikely), be a significant "win", be a nice hack, or simply serve as a road sign indicating that this path is a waste of time (all of the previous results are useful). Are your results general, potentially generalizable, or specific to a particular care?
Key Words • They are used to facilitate keyword index searches, which are greatly reduced in importance now that on-line abstract text searching is commonly used. • However, they are also used to assign papers to review committees or editors, which can be extremely important to your fate. • So make sure that the keywords you pick make assigning your paper to a review category obvious.
Word limit and guidelines • Word limit can vary from 100, 250 or 350 words. • If your abstract runs too long, either it will be rejected or someone will take a chainsaw to it to get it down to size.
The language of Abstracts • Use the past tense to refer to what was done. • Use the present tense to comment on the significance of your research/findings. • Use active verbs whenever possible, e.g. ‘the study tested’ instead of ‘it was tested by the study’. • Use non-evaluative language - report and not to comment on what you have done.
What is a good abstract?
What are people looking for? • Originality and novelty • Overall study quality—design, analyses and interpretation and higher level of evidence • Presentation—clarity and completeness of the write-up. • Significance to the discipline • Appropriateness • Completeness of the research, follow up etc.
A well-written abstract • • • • •
Considers the readers it will encounter Concise Avoids vagueness Informative Self-sufficient and does not refer to the body of the report • Makes concrete, useful recommendations
NEJM • Provide an abstract of not more than 250 words. • It should consist of four paragraphs, labeled Background, Methods, Results, and Conclusions. • They should briefly describe, respectively, the problem being addressed in the study, how the study was performed, the salient results, and what the authors conclude from the results.
LANCET Include an abstract (semi-structured summary), with five paragraphs (Background, Methods, Findings, Interpretation, and Funding), not exceeding 250 words. For randomised trials, the abstract should adhere to CONSORT extensions: abstracts (see Lancet 2008; 371: 281– 83) For intervention studies, the abstract should include the primary outcome expressed as the difference between groups with a confidence interval on that difference (absolute differences are more useful than relative ones). Important secondary outcomes can be included as long as they are clearly marked as secondary.
Structured Abstract Objective/Purpose/Introduction (10% of abstract): The preference is to write one sentence containing a specific purpose statement. Too often writers make the mistake of writing several introductory sentences before stating a purpose. Avoid this unnecessary material. At most, the introduction may include one background statement (one sentence) and then the purpose or specific objective (second sentence). Design or Methods (30-40% of abstract): Describe the study design employed, the study population, the dose or dosage of the drug if used, length of treatment, other collected data like lab tests (if presented in the results), statistics employed. Do not put results in methods or a method in the results. Be clear and concise. Results (30-40% of abstract): What are the most important findings of the research, any specific adverse events or safety results, statistical data (p values)? Conclusions (10% of abstract): List the most important points that the investigators have learned; what are the recommendations. This should be accomplished in one or two sentences. Remember the purpose when writing the conclusion; do not just restate the results.
CONSORT abstract checklist Title Identification of the study as randomised Authors* Contact details for the corresponding author Trial design Description of the trial design (e.g. Parallel, cluster non-inferiority) Methods Participants Eligibility criteria for participants and the settings where the data were collected Interventions intended for each group Objective Specific objective or hypothesis Outcome Clearly defined primary outcome for this report Randomisation How participants were allocated to interventions Blinding (masking) Whether or not participants, care givers, and these assessing the outcomes were blinded to group assignment Results Numbers Number of participants randomised to each group Recruitment Trial status Numbers Number of participants analysed in each group Outcome For the primary outcome a result for each group and the estimated effect size and its precision.Harms Important adverse events or side-effects Conclusion General interpretation of the results Trial registration Registration number and name of trial register Funding Source of funding
www.consort-statement.org
N Engl J Med. 2012 Nov 22;367(21):1988-97 Long-term comparison of endovascular and open repair of abdominal aortic aneurysm. Abstract BACKGROUND: Whether elective endovascular repair of abdominal aortic aneurysm reduces long-term morbidity and mortality, as compared with traditional open repair, remains uncertain. METHODS: We randomly assigned 881 patients with asymptomatic abdominal aortic aneurysms who were candidates for both procedures to either endovascular repair (444) or open repair (437) and followed them for up to 9 years (mean, 5.2). Patients were selected from 42 Veterans Affairs medical centers and were 49 years of age or older at the time of registration. RESULTS: More than 95% of the patients underwent the assigned repair. For the primary outcome of all-cause mortality, 146 deaths occurred in each group (hazard ratio with endovascular repair versus open repair, 0.97; 95% confidence interval [CI], 0.77 to 1.22; P=0.81). The previously reported reduction in perioperative mortality with endovascular repair was sustained at 2 years (hazard ratio, 0.63; 95% CI, 0.40 to 0.98; P=0.04) and at 3 years (hazard ratio, 0.72; 95% CI, 0.51 to 1.00; P=0.05) but not thereafter. There were 10 aneurysmrelated deaths in the endovascular-repair group (2.3%) versus 16 in the open-repair group (3.7%) (P=0.22). Six aneurysm ruptures were confirmed in the endovascular-repair group versus none in the open-repair group (P=0.03). A significant interaction was observed between age and type of treatment (P=0.006); survival was increased among patients under 70 years of age in the endovascular-repair group but tended to be better among those 70 years of age or older in the open-repair group. CONCLUSIONS: Endovascular repair and open repair resulted in similar long-term survival. The perioperative survival advantage with endovascular repair was sustained for several years, but rupture after repair remained a concern. Endovascular repair led to increased long-term survival among younger patients but not among older patients, for whom a greater benefit from the endovascular approach had been expected. (Funded by the Department of Veterans Affairs Office of Research and Development; OVER ClinicalTrials.gov number, NCT00094575.).
Long-term comparison of endovascular and open repair of abdominal aortic aneurysm. Abstract BACKGROUND: Whether elective endovascular repair of abdominal aortic aneurysm reduces long-term morbidity and mortality, as compared with traditional open repair, remains uncertain.
PICO
METHODS: We randomly assigned 881 patients with asymptomatic abdominal aortic aneurysms who were candidates for both procedures to either endovascular repair (444) or open repair (437) and followed them for up to 9 years (mean, 5.2). Patients were selected from 42 Veterans Affairs medical centers and were 49 years of age or older at the time of registration.
RESULTS: More than 95% of the patients underwent the assigned repair. For the primary outcome of all-cause mortality, 146 deaths occurred in each group (hazard ratio with endovascular repair versus open repair, 0.97; 95% confidence interval [CI], 0.77 to 1.22; P=0.81). The previously reported reduction in perioperative mortality with endovascular repair was sustained at 2 years (hazard ratio, 0.63; 95% CI, 0.40 to 0.98; P=0.04) and at 3 years (hazard ratio, 0.72; 95% CI, 0.51 to 1.00; P=0.05) but not thereafter. There were 10 aneurysm-related deaths in the endovascular-repair group (2.3%) versus 16 in the open-repair group (3.7%) (P=0.22). Six aneurysm ruptures were confirmed in the endovascular-repair group versus none in the open-repair group (P=0.03). A significant interaction was observed between age and type of treatment (P=0.006); survival was increased among patients under 70 years of age in the endovascular-repair group but tended to be better among those 70 years of age or older in the open-repair group.
CONCLUSIONS: Endovascular repair and open repair resulted in similar long-term survival. The perioperative survival advantage with endovascular repair was sustained for several years, but rupture after repair remained a concern. Endovascular repair led to increased long-term survival among younger patients but not among older patients, for whom a greater benefit from the endovascular approach had been expected. (Funded by the Department of Veterans Affairs Office of Research and Development; OVER ClinicalTrials.gov number, NCT00094575.).
N Engl J Med. 2012 Nov 29;367(22):2089-99. Effects of dalcetrapib in patients with a recent acute coronary syndrome. BACKGROUND: In observational analyses, higher levels of high-density lipoprotein (HDL) cholesterol have been associated with a lower risk of coronary heart disease events. However, whether raising HDL cholesterol levels therapeutically reduces cardiovascular risk remains uncertain. Inhibition of cholesteryl ester transfer protein (CETP) raises HDL cholesterol levels and might therefore improve cardiovascular outcomes. METHODS: We randomly assigned 15,871 patients who had had a recent acute coronary syndrome to receive the CETP inhibitor dalcetrapib, at a dose of 600 mg daily, or placebo, in addition to the best available evidence-based care. The primary efficacy end point was a composite of death from coronary heart disease, nonfatal myocardial infarction, ischemic stroke, unstable angina, or cardiac arrest with resuscitation. RESULTS: At the time of randomization, the mean HDL cholesterol level was 42 mg per deciliter (1.1 mmol per liter), and the mean low-density lipoprotein (LDL) cholesterol level was 76 mg per deciliter (2.0 mmol per liter). Over the course of the trial, HDL cholesterol levels increased from baseline by 4 to 11% in the placebo group and by 31 to 40% in the dalcetrapib group. Dalcetrapib had a minimal effect on LDL cholesterol levels. Patients were followed for a median of 31 months. At a prespecified interim analysis that included 1135 primary end-point events (71% of the projected total number), the independent data and safety monitoring board recommended termination of the trial for futility. As compared with placebo, dalcetrapib did not alter the risk of the primary end point (cumulative event rate, 8.0% and 8.3%, respectively; hazard ratio with dalcetrapib, 1.04; 95% confidence interval, 0.93 to 1.16; P=0.52) and did not have a significant effect on any component of the primary end point or total mortality. The median C-reactive protein level was 0.2 mg per liter higher and the mean systolic blood pressure was 0.6 mm Hg higher with dalcetrapib as compared with placebo (P<0.001 for both comparisons). CONCLUSIONS: In patients who had had a recent acute coronary syndrome, dalcetrapib increased HDL cholesterol levels but did not reduce the risk of recurrent cardiovascular events. (Funded by F. Hoffmann-La Roche; dal-OUTCOMES ClinicalTrials.gov number, NCT00658515.).
N Engl J Med. 2013 Jan Antibiotics as part of the management of severe acute malnutrition. BACKGROUND: Severe acute malnutrition contributes to 1 million deaths among children annually. Adding routine antibiotic agents to nutritional therapy may increase recovery rates and decrease mortality among children with severe acute malnutrition treated in the community. METHODS: In this randomized, double-blind, placebo-controlled trial, we randomly assigned Malawian children, 6 to 59 months of age, with severe acute malnutrition to receive amoxicillin, cefdinir, or placebo for 7 days in addition to ready-to-use therapeutic food for the outpatient treatment of uncomplicated severe acute malnutrition. The primary outcomes were the rate of nutritional recovery and the mortality rate. RESULTS: A total of 2767 children with severe acute malnutrition were enrolled. In the amoxicillin, cefdinir, and placebo groups, 88.7%, 90.9%, and 85.1% of the children recovered, respectively (relative risk of treatment failure with placebo vs. amoxicillin, 1.32; 95% confidence interval [CI], 1.04 to 1.68; relative risk with placebo vs. cefdinir, 1.64; 95% CI, 1.27 to 2.11). The mortality rates for the three groups were 4.8%, 4.1%, and 7.4%, respectively (relative risk of death with placebo vs. amoxicillin, 1.55; 95% CI, 1.07 to 2.24; relative risk with placebo vs. cefdinir, 1.80; 95% CI, 1.22 to 2.64). Among children who recovered, the rate of weight gain was increased among those who received antibiotics. No interaction between type of severe acute malnutrition and intervention group was observed for either the rate of nutritional recovery or the mortality rate. CONCLUSIONS: The addition of antibiotics to therapeutic regimens for uncomplicated severe acute malnutrition was associated with a significant improvement in recovery and mortality rates.
N Engl J Med. 2012 Nov 22;367(21):1979-87. Low-dose aspirin for preventing recurrent venous thromboembolism. BACKGROUND: Patients who have had a first episode of unprovoked venous thromboembolism have a high risk of recurrence after anticoagulants are discontinued. Aspirin may be effective in preventing a recurrence of venous thromboembolism. METHODS: We randomly assigned 822 patients who had completed initial anticoagulant therapy after a first episode of unprovoked venous thromboembolism to receive aspirin, at a dose of 100 mg daily, or placebo for up to 4 years. The primary outcome was a recurrence of venous thromboembolism. RESULTS: During a median follow-up period of 37.2 months, venous thromboembolism recurred in 73 of 411 patients assigned to placebo and in 57 of 411 assigned to aspirin (a rate of 6.5% per year vs. 4.8% per year; hazard ratio with aspirin, 0.74; 95% confidence interval [CI], 0.52 to 1.05; P=0.09). Aspirin reduced the rate of the two prespecified secondary composite outcomes: the rate of venous thromboembolism, myocardial infarction, stroke, or cardiovascular death was reduced by 34% (a rate of 8.0% per year with placebo vs. 5.2% per year with aspirin; hazard ratio with aspirin, 0.66; 95% CI, 0.48 to 0.92; P=0.01), and the rate of venous thromboembolism, myocardial infarction, stroke, major bleeding, or death from any cause was reduced by 33% (hazard ratio, 0.67; 95% CI, 0.49 to 0.91; P=0.01). There was no significant between-group difference in the rates of major or clinically relevant nonmajor bleeding episodes (rate of 0.6% per year with placebo vs. 1.1% per year with aspirin, P=0.22) or serious adverse events. CONCLUSIONS: In this study, aspirin, as compared with placebo, did not significantly reduce the rate of recurrence of venous thromboembolism but resulted in a significant reduction in the rate of major vascular events, with improved net clinical benefit. These results substantiate earlier evidence of a therapeutic benefit of aspirin when it is given to patients after initial anticoagulant therapy for a first episode of unprovoked venous thromboembolism. (Funded by National Health and Medical Research Council [Australia] and others; Australian New Zealand Clinical Trials Registry number, ACTRN12605000004662.).
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The Lancet, Volume 380, Issue 9852, Pages 1491 - 1497, 27 October 2012
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Job strain as a risk factor for coronary heart disease: a collaborative meta-analysis of individual participant data Background Published work assessing psychosocial stress (job strain) as a risk factor for coronary heart disease is inconsistent and subject to publication bias and reverse causation bias. We analysed the relation between job strain and coronary heart disease with a meta-analysis of published and unpublished studies. Methods We used individual records from 13 European cohort studies (1985—2006) of men and women without coronary heart disease who were employed at time of baseline assessment. We measured job strain with questions from validated job-content and demand-control questionnaires. We extracted data in two stages such that acquisition and harmonisation of job strain measure and covariables occurred before linkage to records for coronary heart disease. We defined incident coronary heart disease as the first non-fatal myocardial infarction or coronary death. Findings 30 214 (15%) of 197 473 participants reported job strain. In 1·49 million person-years at risk (mean follow-up 7·5 years [SD 1·7]), we recorded 2358 events of incident coronary heart disease. After adjustment for sex and age, the hazard ratio for job strain versus no job strain was 1·23 (95% CI 1·10— 1·37). This effect estimate was higher in published (1·43, 1·15—1·77) than unpublished (1·16, 1·02— 1·32) studies. Hazard ratios were likewise raised in analyses addressing reverse causality by exclusion of events of coronary heart disease that occurred in the first 3 years (1·31, 1·15—1·48) and 5 years (1·30, 1·13—1·50) of follow-up. We noted an association between job strain and coronary heart disease for sex, age groups, socioeconomic strata, and region, and after adjustments for socioeconomic status, and lifestyle and conventional risk factors. The population attributable risk for job strain was 3·4%. Interpretation Our findings suggest that prevention of workplace stress might decrease disease incidence; however, this strategy would have a much smaller effect than would tackling of standard risk factors, such as smoking.
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Interactive effects of fitness and statin treatment on mortality risk in veterans with dyslipidaemia: a cohort study Background Statins are commonly prescribed for management of dyslipidaemia and cardiovascular disease. Increased fitness is also associated with low mortality and is recommended as an essential part of promoting health. However, little information exists about the combined effects of fitness and statin treatment on all-cause mortality. We assessed the combined effects of statin treatment and fitness on all-cause mortality risk. Methods In this prospective cohort study, we included dyslipidaemic veterans from Veterans Affairs Medical Centers in Palo Alto, CA, and Washington DC, USA, who had had an exercise tolerance test between 1986, and 2011. We assigned participants to one of four fitness categories based on peak metabolic equivalents (MET) achieved during exercise test and eight categories based on fitness status and statin treatment. The primary endpoint was all-cause mortality adjusted for age, body-mass index, ethnic origin, sex, history of cardiovascular disease, cardiovascular drugs, and cardiovascular risk factors. We assessed mortality from Veteran's Affairs’ records on Dec 31, 2011. We compared groups with Cox proportional hazard model. Findings We assessed 10 043 participants (mean age 58·8 years, SD 10·9 years). During a median follow-up of 10·0 years (IQR 6·0—14·2), 2318 patients died, with an average yearly mortality rate of 22 deaths per 1000 person-years. Mortality risk was 18·5% (935/5046) in people taking statins versus 27·7% (1386/4997) in those not taking statins (p<0·0001). In patients who took statins, mortality risk decreased as fitness increased; for highly fit individuals (>9 MET; n=694), the hazard ratio (HR) was 0·30 (95% CI 0·21—0·41; p<0·0001) compared with least fit (≤5 METs) patients (HR 1; n=1060). For those not treated with statins, the HR for least fit participants (n=1024) was 1·35 (95% CI 1·17—1·54; p<0·0001) and progressively decreased to 0·53 (95% CI 0·44—0·65; p<0·0001) for those in the highest fitness category (n=1498). Interpretation Statin treatment and increased fitness are independently associated with low mortality among dyslipidaemic individuals. The combination of statin treatment and increased fitness resulted in substantially lower mortality risk than either alone, reinforcing the importance of physical activity for individuals with dyslipidaemia.
A Check List of Do's and Don't •Background no more than two sentences, including the purpose . •Abbreviations defined on their first use •Every result has a corresponding method ; Dose, dosage, population studied, duration or time period, other measurements to be included in the results, and setting of the research are included •Dose/dosage contains units and time duration •Conclusion extracts the one or two most important point •Generally no table should be included; No references should be included. •Don't present work you are going to do or that should be done •Don't overuse familiar terms or acronyms. •Don't add a statement in conclusion that is a stretch of the results or not supported by the data •Don't use a lot of space reporting negative findings (negative abstracts are always harder to get accepted) •Don't repeat or paraphrase title in purpose of abstract (common mistake)
A Check List of Do's and Don't • • • •
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Don't use a lot of space reporting negative findings (negative abstracts are always harder to get accepted) Don't repeat or paraphrase title in purpose of abstract (common mistake) No jargon is included that may confuse the reader References - you may include a reference (abbreviated) if highly relevant to the current research. This is not the norm, however, and if in doubt whether to use, don't. Avoid abbreviations in title if possible Authors included had a specific contribution to the study Have an independent researcher review the abstract; let the abstract sit for a day or two, then edit again.
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Reason for rejection
No hypothesis Methods unclear No summary of essential results No conclusion No new information Lack of data Numbers in study too small, incomplete follow up • No controls • Conclusion is not supported by the data • Promotional/too commercial in nature Methods are not clear or are inappropriate Study in progress/not completed
Conclusion â&#x20AC;˘ Writing an efficient abstract is hard work, but will repay you with increased impact by enticing people to read your publications. â&#x20AC;˘ Make sure that all the components of a good abstract are included in the next one you write!