Katherine Pérez, Marc Marí-Dell’Olmo, Carme Borrell, Manel Nebot , Joan R Villalbí, Elena Santamariña, Aurelio Tobias. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. Bulletin of the World Health Organization (in press).
TITLE: Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series analysis Authors Katherine Péreza,b, Marc Marí-Dell’Olmoc,b,a, Carme Borrella,b,d, Manel Nebota,b,d , Joan R Villalbía,b,d, Elena Santamariñaa, Aurelio Tobiase a Agència de Salut Pública de Barcelona. Pl Lesseps, 1. E08023 Barcelona. Spain b CIBER en Epidemiología y Salud Pública (CIBERESP), Spain c Institut d’Investigació en Atenció Primària Jordi Gol d Universitat Pompeu Fabra. Departament de Ciències Experimentals i de la Salut e Escuela Nacional de Sanidad, Instituto de Salud Carlos III Keywords: Road Safety, Motorcycles, Traffic accidents, Injuries, Evaluation, Policy
Correspondence to: Katherine Pérez. Agència de Salut Pública de Barcelona. Pl Lesseps, 1 E 08023 Barcelona Spain Fax. + 34 e-mail: cperez@aspb.cat
Contributions KP: Conceived the study and designed the study and performed some statistical analysis. MMD: Performed statistical analyses. CB: Assisted conceptualizing ideas. AT assisted refining the statistical analyses. KP Wrote the draft of the manuscript and all authors contributed to the interpretation of the results and the revision of the manuscript. Conflict of interest The authors express no conflicts of interest.
Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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ABSTRACT Objectives: To assess the impact on the number of road injuries in Barcelona of a new motorcycle regulation that allowed people who held a car license for at least three years, to drive a light motorcycle (<125cc) without passing a specific driving test. Design: Quasi-experimental evaluation study using comparison groups and time series analysis for 2002 to April 2008. Main outcome measures: The number of people injured was estimated through Poisson regression models, adjusting for trend, seasonality, existence of a driver’s license penalty points system, Results: After the new driving regulation it was more likely to be injured in a light motorcycle than in the period before: relative risk (RR) = 1.46 (95%CI 1.34, 1.60); Although in a smaller amount, the risk for heavy motorcycles also increased RR = 1.15 (95%CI 1.02, 1.29). The risk of being injured, as a moped or car occupant did not change between pre and post law periods (0.92, [95%CI 0.83, 1.01], for moped; 1.06, [95%CI 0.97, 1.16] for car). In conclusion, facilitating access of car drivers to motorcycles without a prior specific test increases the number of road injuries involving a motorcycle. Nonetheless in addition to a change in drivers regulation, other factors may have contributed also to this increase, such the pressure to reduce car use.
Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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BACKGROUND
Road traffic injuries are a major cause of mortality and morbidity worldwide. Among all user, two-wheeled motor vehicle users and pedestrians have higher vulnerability1. In Europe (EU-25) in 2005 there were 441,247 road traffic deaths2, and 21.1% were among two-wheeled motor vehicle users in the 14 European Union countries3. Compared to 1996, in 2005 the number of fatalities among motorcyclists in the EU showed an increase (+22%) while deaths related to other modes of transport declined (pedestrian -37%, pedal cyclists -42%, moped riders -41%, and car –28%)4. In Spain motorcycles represented approximately 7.2% of all motor vehicles5, and motorcyclists accounted for 8.4% of all road traffic fatalities, although a decreasing trend is evident from 19986 until 2004, when they accounted for 7.4% of all road traffic injury cases7. Recently a dramatic increase of 29.8% of cases fatalities among motorcycles users has been also reported in 2007 regarding 20068.
Until September 2004 users of motorcycles (> 50 cc) in Spain had to obtain a permit that required passing a written test on motorcycle operation and traffic laws, and a skills test in a circuit. In October 2004 a new regulation was passed which allowed car drivers, provided they had held a car license for at least three years, to drive a motorcycle of up to 125 cc. and 15 hp. without any further license or test requirement. Similar regulations had previously been passed in other European countries but no evaluation studies have been published. To our knowledge, there is only one study, carried out in 1997-1999 that analyses the effect of motorcycle licensing regulations on mortality rates9. It concludes that specific motorcycle licensing policies (such as skill test for a motorcycle permit, driver training, longer duration of learner’s permit, three or Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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more learnerâ&#x20AC;&#x2122;s permit restrictions and requiring a full helmet to be worn), appear to be associated with lower mortality rates.
Barcelona, with 1.6 million inhabitants, is the capital of Catalonia, in NE Spain. Motorcycles are a very popular vehicle in the city probably favored by the Mediterranean climate and the high density of the city. In 2005 it has been reported that there were 163 motorcycles per 1,000 inhabitants, (compared with, for example, Rome, 161; Madrid, 30; and London, 20). Every year there are more than 10,000 motor vehicle crashes within city limits resulting in 13,000 people being injured, and around 50 deaths. In 2005, 28% of injured were car occupants, 27% motorcyclists, 25% moped users, 13% pedestrians, 2.4% cyclists, and 4,6% users of other vehicles. The Injury Severity Score (ISS) (provided by the city emergency surveillance system) was higher for motorcyclists and pedestrians than for car occupants. 15.4% of motorcyclists had moderate injuries (ISS 4 to 8) and 1.7% severe injuries (ISS 9 to 75), moped 13.7% and 1.8% respectively, pedestrians 23.7% and 3.4%, and car occupants 5.8% and 0.4% respectively. We assessed the.
The objective of this study is to assess the impact on the number of road injuries in Barcelona of a new motorcycle regulation that allowed people who held a car license for at least three years, to drive a light motorcycle (<125cc) without passing a specific driving test. The hypothesis behind this analysis is that relaxing access to light motorcycles, without licensing requirements will increase the likelihood of crashes involving this type of vehicle.
Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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MATERIALS AND METHODS Design and population of the study The study design is that of a quasi-experimental evaluation with a comparison group and time series analysis. The targeted group consists of people injured while driving or being a passenger of a light motorcycle (51cc to 125cc). The comparisons groups included heavy motorcycles (>125cc), moped (≤ 50cc), and car occupants injured in a collision within the city limits. Non-injured involved in crashes and pedestrians were excluded from the analysis.
Period of study The study covers two periods of three years. The period prior to enforcement of the new regulation runs from January 1st 2002 to September 30th 2004, while that after its introduction is from October 1st 2004 to April 30th 2008.
Sources of information The source of information is the city police registry of collisions. In Barcelona there is a special department in the city police for traffic collisions, which ensures a comprehensive coverage of all crashes with people injured. Specially trained officers, using a standardized protocol, do the reporting. All crashes involving property damage or injuries are included. The registry includes information about the driver, persons injured, the vehicle and the circumstances of the collision.
Regarding the quality of data there were some inconsistencies. Of the 22,161 injured reported as motorcyclists, 284 (1.4%) were listed as moped occupants and 76 were car occupants, both were excluded from the analysis. The opposite also occurred: out of Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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32,992 reported as occupants of vehicles other than motorcycles, there were 1,302 (3.9%) listed as passengers of light motorcycles and 163 (0.5%) of heavy motorcycles. These were included in the analysis.
The number of new registrations of motorcycles was obtained from the Institut Municipal d’Estadística10 for 2002 to September 30th 2007.
Variables and indicators Outcome measures are the number of people injured (including fatal injuries). The number of deaths was not analyzed separately because figures were too low to allow a time series analysis (6 in 2002, 16 in 2003, 12 in 2004, 17 in 2005, 21 in 2006, and 17 in 2007).
Motorcycles have been classified from brand and model according its auto cubic capacity. Light motorcycles are those from 51cc to 125cc, and heavy motorcycles are those with more that 125cc. There were motorcycles without detailed information, thus 21,3% of motorcycles recorded could not be classified 4,350 from the pre-law period, 6,217 from the post-law period).
A penalty points system for driving offences was introduced in the driving licenses for Spain on July 1st 2006. This situation was taken into account in the model to control for this effect.
Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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Statistical analysis. The time series of outcome measures, previously defined, were analyzed using Poisson regression models. Potential confounding for trend and seasonal patterns were adjusted for using a linear combination of sine and cosine functions11. After trend and seasonal patterns had been controlled for, an intervention analysis was carried out by fitting a dummy variable to compare the pre- and post-law periods. Thus, the model for each outcome
can
be
summarized
as
follows:
ln[E(Yt)]=b0+b1×t+b2×sin(2πt/T)+b3×cos(2πt/T)+b4×Xt, where T is the number of periods described by each sinusoidal function (for example, T=12 months), t is the time period (t=1 for January, t=2 for February, etc.), where Xt = 1 identifies the postintervention period and Xt = 0 otherwise.
Dependent variables were people injured as occupants of light motorcycles (51cc to 125cc), heavy motorcycles (>125cc), moped (≤50cc) car, and motorcycles of unknown cubic capacity. The trend was not statistically significant for light motorcycles. Therefore the final model was not adjusted for trend for light motorcycles. The penalty points system was not significant for any dependent variable, therefore was not included to fit the models. Models were fitted also adjusting for the registration of new motorcycles.
Relative risks (RR) and 95% confidence intervals (CI) and expected distribution, had the motorcycle license regulation not been passed, with 95% confidence intervals, were derived from the adjusted models. The attributable fraction (AF) was calculated from RR (AF=(RR-1)/RR)12 to estimate the number of attributable people injured in
Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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collisions. Statistical analyses were carried out using Stata statistical software, release
10.013.
RESULTS During the pre-law period the mean number of people injured involving light motorcycles showed a decreasing trend (non significant), while in the post-law period a significant increasing trend was observed (figure 1). Pre-law mean was 104.6 injured per month, while post-law mean was 154.3 (table 1). Since October 2004, the number of new registrations of light motorcycles increased dramatically (figure 1).
Injuries involving heavy motorcycles also increased over the period (pre-law mean 94.7, post-law mean 121.6). At the same time the number of new registrations of heavy motorcycles showed an steady increase for the whole period, without any change since October 2004 (figure 1). On the other hand, occupants of moped and car injured decreased over time (213.6 to 174.8 for moped, 357.7 to 277.9 for car) (Table 1).
After controlling for trend, and seasonality by fitting Poisson regression models, it was significantly more likely to be injured as a motorcyclist, in both light and heavy models, in the post-law period. The relative risk (RR) of being injured in a light motorcycle in the post-period compared to the pre-period was: 1.46 (95%CI 1.34, 1.60), and for heavy motorcycles was 1.15 (95%CI 1.02, 1.29). The risk increased over the years for light motorcycles (18%, 38%, 68% and 77% after 1st, 2nd 3rd and 4th year of intervention respectively), and seems stable for the last years for heavy motorcycles (19% after 1st year, 31% for 2nd and 3rd and 37% respectively) (Table 2). The RR for the trend in the post-law period was 1.013 (95%CI 1.010, 1.016) for light motorcycles and 1.004 Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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(95%CI 1.001, 1.007) for heavy motorcycles. There has been a change in the trend of RR = 0.0158 and 0.0041 respectively. It implies that during the post-law period there is a significant increase of 1,6% of people injured per month for light motorcycles and 0.4% for heavy motorcycles (non statistically significant). Although the trend for both type of motorcycles increases, they are significantly different, being greater for light motorcycles. Confidence intervals for post-law trend and third year after intervention do not overlap. The relative risk for motorcycles of unknown cubic capacity was 1.34 (95%CI 1.015, 1.057).
The risk of being injured as a moped or car occupant was not statistically different between both pre and post law periods (0.92, [95%CI 0.83, 1.01], for moped; 1.06, [95%CI 0.97, 1.16] for car). In this case the post-law period trend continued to decrease and did not changed significantly from the pre-law period (Table 2).
In order to take into account the exposure, the intervention was adjusted for the number of registered vehicles from residents in the city. Once adjusted, the change of the law showed no effect on the number of injured for all type of vehicles, which suggest that the increased risk observed in the number of injured is mainly due to and increase in exposure. The adjusted RR for light motorcycles was 1.03 (95%CI 0.80, 1.34), for heavy motorcycles 1.08 (95%CI 0.98, 1.12).
Figure 2 shows the observed distribution of the number of injured and the expected distribution, had the motorcycle license regulation not been passed, with 95% confidence intervals, since 2002. For light motorcyclists observed cases are higher than expected cases and this difference increases along time. Observed cases of heavy Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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motorcyclists are also higher than expected but stable for the last year. There are 2,099 more injured of light motorcycles and 691 motorcycles than expected. Observed cases of moped and car occupants overlap expected cases (table 1).
Table 3 describes sex and age distribution of people injured by vehicle and pre or post period. It includes the description of cases that were not included to fit the models due to missing information on cubic capacity. These cases are similar to light motorcyclists injured. For all vehicles there is a higher proportion of females the post-law period and a higher proportion of injured 31 to 45 years old.
Table 4 shows the characteristics of drivers involved in road traffic crash with injured. As expected, the proportion of light motorcyclists with a car driving license increases dramatically during the post period. Age and sex of drivers of unknown cubic capacity are more similar to light motorcyclists. However around one third have a moped license, which means that might be moped users instead of motorcyclists.
DISCUSSION This study assesses the impact of a motorcycle license law. These results strongly suggest that a regulation relaxing requirements for access to drive a light motorcycle to experienced car drivers without specific testing of motorcycle skills increases the number of road injuries. This increase is related to exposure to motorcycles. The increase is parallel to the number of new light motorcycles and the risk of injuries does not increase if the new registration is taken into account. However other factors might have affected also the increase, as the number of injured users of heavy motorcycles increased somewhat during two years and stabilized the third year. Users of other Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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vehicles such moped or car injured decreased over time, and were not affected by the motorcycle license law.
The strengths of the study are: availability of comparable data on number of injured, before and after the change of the law, which allowed also to control for major confounding factors such regression to the mean, change in general trend, and traffic migration14; the high number of motorcycles circulating per person give more power to the statistical analysis; the type of statistical analysis carried out, Poisson regression time series, which allow to work without denominators; and the possibility to have comparison groups. Although the study has been carried out in a single city, we believe that as a policy evaluation study it has external validity.
The results of the study confirm the hypothesis that providing easy access to light motorcycles, without requiring prior skill development and testing, will increase the likelihood of crashes involving this type of vehicle. We also found a minor increase in the number of injuries related to heavy motorcycles occupants. Several factors could have influenced this increase. Firstly, the number of new registrations was increasing steadily before 2004 (the year of the regulatory change), and continued afterwards, without any change in the trend. Secondly since 2004 there were other initiatives to reduce the use of cars in the city, such as establishing expensive parking areas and redesigning areas for traffic calming, which can be reflected also in the decreasing number or car injured along time. In 2004 there were 7,158 pay street places, while in 2007 there were 40,482. Total hectares for pedestrians increased 12.8% since 2004. Rising demographics and the cost of housing drive people to live outside city limits in other metropolitan area towns, although they study or work in the city. Thus forcing Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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increased use of private transportation as the needed mass transport infrastructures (expanded subway and local trains systems), in the metropolitan area are slow to develop.
Regarding injured of light motorcycles occupants, it is clear that the change of the law had a strong impact increasing the number of injured. The increasing trend continues more than three years later of the regulatory change, by 1,6% per month, probably favored by the factors explained before. In addition, some drivers of light motorcycles involved in crashes could have been driving mopeds previously. This could explain also partially the decrease in the use of mopeds. As reported by Seguí-Gómez, regardless of their effectiveness as an injury prevention intervention, the prior educational programs and fees apparently acted as a de facto ‘‘barrier’’ to obtaining a motorcycle operators’ license for some23. Our data does not allow us to assess to what extent the increased risk is due to lack of adequate driving training. Driver inexperience with motorcycle riding has been shown to be a risk factor for motorcycle collisions15,16. Research of graduated licensing programs for motorcyclists suggests that specific restrictions such as supervision, daylight driving only, and blood-alcohol concentration limits of zero reduce collisions17.
A possible relationship with increased sales of motorcycles and increased mortality rates has been reported previously18. Paulozzi reported that, according to the National Highway Traffic Safety Administration, mortality rates from crashes among motorcycle riders in the United States increased from 21.0 per 100 million motorcycle miles traveled in 1997 to 38.4 per 100 million motorcycle miles traveled in 2003. At the same time, annual domestic sales of new, on-road motorcycles increased from 247,000 in Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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1997 to 648,000 in 2003. Mortality rates were higher for drivers or passengers of newer motorcycles. The author suggests two possible explanations: an increased exposure from more extensive use of motorcycles when they are new, and inexperience with motorcycle riding.
Some other studies have assessed the impact of policy legislation on crash rates, but nearly all referred to the use of alcohol19, bicycle helmet20, motorcycle helmet21 or more recently to the penalty points system22. There is only one study that assesses the effect of state motorcycle licensing laws on motorcyclist mortality rates. Specific motorcycle licensing policies have been reported to be associated with lower mortality rates9. Lower mortality rates were observed in states requiring a skills test for a motorcycle permit (rate ratio (RR), 0.76; CI, 0.69, 0.84), driver training (RR, 0.80; CI, 0.74, 0.86), longer duration of learner's permits (95 to 190 days (RR, 0.86; CI, 0.79, 0.95) and >190 days (RR, 0.87; CI, 0.81, 0.93)), three or more learner's permit restrictions (RR, 0.78; CI, 0.73, 0.84), and requiring a full helmet to be worn (RR, 0.76; CI, 0.71, 0.81).
As limitations of the study we must mention that good denominators of mobility, such as vehicle-kilometers traveled for motorcycles, are not available. As a proxy we used the number of new registrations of vehicles. However the type of analysis conducted, allows an analysis without denominators since it adjusts for linear trend and seasonality. It has been impossible to assess the impact adjusting for injury severity as there is no information until 2005. From the city emergency surveillance system it has been reported that the number of motorcyclists who attended an emergency department increased by 59.6% from 2003 (4,117) to 2006 (6,571), and the number of motorcyclists hospitalized increased by 87.5% from 2003 (312) to 2006 (585). Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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Another limitation that could have influenced results is the possibility of misclassification of type of motorcycle due to insufficient information on the vehicle. We reduce the likelihood of misclassification by using brand and model. On the other hand, the fact that 21,3% of motorcycles was excluded from the analysis will not change the sense of the results, but will reduce the magnitude. If we add unknown motorcyclists to light motorcyclists, the risk is reduced but still significant (RR, 1.25; CI, 1.18, 1.33). If we add them to heavy motorcyclists the risk increased (RR, 1.17; CI, 1.11, 1.124).
In conclusion, a regulation facilitating access of car drivers to motorcycles without a prior specific test increases the number of road injuries involving a motorcycle, favored by other factors such initiatives to reduce car use. Policy makers and legislators should to consider the implications of regulation changes such as this one, where important gains for industry are obtained by facilitating access to a vulnerable vehicle, but at the cost of a notable increase in road traffic injuries among the population.
Acknowledgments The authors would like to thank Sector de Prevenció, Mobilitat i Seguretat of the Ajuntament de Barcelona, specially Mercé Navarro, and Guàrdia Urbana de Barcelona, specially Joan Mañosa and Manuel Haro for their contribution providing the data.
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Table 1. Observed and expected number of injured in road collisions and mean monthly by type of vehicle. Barcelona January 2002 to April 2008. Motorcycles Light Heavy Motorcycle Motorcycle (51cc to 125cc) (>125cc) Mean Mean n n monthly monthly
Moped Car (≤ ≤ 50cc) n
Mean monthly
n
Mean monthly
Pre law Jan 2002-Sept 2002 Oct 2002-Sept 2003 Oct 2003-Sept 2004
956 1,312 1,183
106.2 109.3 98.6
870 1,114 1,146
99.7 92.8 95.5
1,937 2,700 2,413
215.2 225.0 201.1
3,404 4,466 3,933
378.2 372.2 327.8
Total Observed
3,451
104.6
3,130
94.7
7,050
213.6
11,803
357.7
Post law Oct 2004-Sept 2005 Oct 2005-Sept 2006 Oct 2006-Sept 2007 Oct 2006-April 2008
1,482 1,731 2,119 1,301
123.5 144.3 176.6 185.9
1,352 1,488 1,487 902
112.7 124.0 123.9 128.9
2,267 2,023 2,006 1,221
188.9 168.6 167 174.4
3,805 3,421 3,130 1,592
317.1 285.1 260.8 227.4
Total Observed
6,633
154.3
5,259
121.6
7.517
174.8
11,948
277.9
n
95% CI*
n
95% CI
n
95% CI
n
95% CI
4,534
3,849 to 5,218
4,038
3,881 to 5,115
8,217
7,246 to 9,188
11,267
10,028 to 12,507
2,099
1,415 to 2,784
691
34 to 1,348
-700
-700 to 271
681
-559 to 1,920
Expected Observed – Expected * Confidence Interval 95%
Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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.Table 2. Relative Risk of people injured in collisions by type of vehicle. Barcelona, January 2002 to April 2008. (Time series analysis with Poisson regression models). Motorcycles Light Motorcycle (51cc to 125cc) RR p Trend Pre Post Trend change post-pre
Intervention
Moped
Heavy Motorcycle (>125cc)
(≤ ≤ 50cc)
Car
RR
p
RR
p
RR
p
0.997 1.013
ns < 0.001
0.999 1.004
ns < 0.05
0.996 0.997
< 0.05 ns
0.993 0.991
< 0.001 < 0.001
1.0158
< 0.001
1.0041
ns
1.0012
ns
0.998
ns
RR (IC95%)
AF
Attar. Event s RR (IC95%)
1.46 (1.34,1.60)
32%
2,091
15%
226
28%
477
40%
858
44%
566
1.15 (1.02,1.29)
AF
Attar. Event s
RR (IC95%)
13%
682
0.92 (0.83,1.01)
16%
216
24%
352
24%
352
27%
244
AF
Attar. Event s
RR (IC95%)
AF
Attar. Events
-9%
-654
1.06 (0.97,1.16)
6%
676
-4%
-94
3%
111
-11%
-225
1%
34
-8%
-151
-1%
-32
2%
24
-9%
-138
Intervention After 1 year After 2 years After 3 years After 3years & 7 months
1.18 (1.07,1.29) 1.38 (1.26,1.50) 1.68 (1.55,1.83) 1.77 (1.59,1.96)
1.19 (1.09,1.42) 1.31 (1.20,1.42) 1.31 (1.20,1.42) 1.37 (1.23,1.52)
0.96 (0.86,1.07) 0.90 (0.78,1.04) 0.93 (0.78,1.12) 1.02 (0.81,1.28)
Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
1.03 (0.93,1.14) 1.005 (0.88,1.15) 0.997 (0.84,1.19) 0.922 (0.74,1.15)
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Table 3. Characteristics of road injured among occupants of motorcycles, moped and car according the pre and post law period. Barcelona, January 2002 to April 2008.
Light Motorcycle (51cc to 125cc) Pre† post‡ n=3,451 n=6,633 Gender Male 66.6 Female 29.1 Unknown 4.3 Age 0-13 years 0.8 14-15 years 3.8 18-30 years 49.7 31-45 years 34.2 36-50 years 10.0 46-65 years 0.9 66-98 years 0.6 Unknown 0.8 †Pre: 1st January 2002 - September 2004 ‡Post: 1st October 2004 - 30th April 2008
Motorcycles Heavy Motorcycle (>125cc) pre post n=3,130 n=5,229
Moped
Motorcycle Unknown cc
Car (≤ ≤ 50cc)
pre n=4,350
post n=6,217
pre n=7,050
post n=7,515
pre n=11,803
post n=11,948
67.7 32.3 0
81.6 13.9 4.5
84.1 15.9 0
65.7 30.0 4.3
66.4 33.6 0
64.7 31.4 4.0
64.9 35.1 .0
55.6 39.9 4.5
57.4 42.5 0.1
0.5 4.6 47.6 36.2 10.3 0.5 0.3 0.5
0.3 0.4 41.9 43.9 11.8 0.8 0.9 0.3
0.4 0.5 34.1 46.7 16.8 0.8 0.7 0.4
0.5 6.2 52.5 29.7 9.9 0.5 0.7 0.5
0.4 5.3 49.0 34.6 9.8 0.4 0.4 0.4
0.4 13.1 68.6 14.3 2.9 0.3 0.4 0.4
0.3 13.3 64.3 18.1 3.5 0.3 0.2 0.3
3.4 1.6 44.6 26.0 18.7 4.1 1.5 3.4
4.0 1.5 39.8 29.1 19.9 4.4 1.3 4.0
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Table 4. Characteristics of motorcycles, moped and car drivers involved in road injured crashes according the pre and post law period. Barcelona, January 2002 to April 2008. Light Motorcycle (51cc to 125cc) Pre† post‡ n=3,551 n=6,798 Gender Male 69.8 71.3 Female 21.2 24.5 Unknown 9.1 4.2 Age 0-13 years 0.1 0 14-17 years 2.7 3.8 18-30 years 47.0 45.1 31-45 years 34.3 35.7 46-65 years 9.7 10.4 > 65 years 0.8 0.6 Unknown 0.1 0 Day of collision Weekend 19.5 18.5 Day time 8h to 20h 73.3 76.0 Type of driving license A (Motorcycle) 73.9 42.7 B (Car) 4.1 42.4 L (Moped) 11.3 6.8 Other 0 0 Unknown 10.6 8.1 †Pre: 1st January 2002 - September 2004 ‡Post: 1st October 2004 - 30th April 2008
Motorcycles Heavy Motorcycle (>125cc) pre post n=3,317 n=5,489
Moped
Motorcycle Unknown cc
Car (≤ ≤ 50cc)
pre n=4,640
post n=6,439
pre n=6,947
post n=7,668
pre n=35,482
post n=42,318
87.0 5.8 7.2
88.9 7.8 3.3
69.0 22.7 8.3
69.6 25.8 4.6
69.7 24.0 6.4
70.6 26.3 3.1
69.2 14.0 16.8
71.6 15.9 12.5
0 .1 .2 37.6 45.3 12.7 0.5
0 .2 30.9 47.2 17.0 0.7
0 5.0 48.9 30.3 10.1 0.6 0
0 4.4 45.8 34.2 10.2 0.5 0
0 11.3 66.1 15.8 3.4 0.3 7.0
0 11.4 61.5 19.4 4.1 0.3 6.5
0 .1 31.9 28.4 21.8 3.4 0
0 0 28.8 30.5 23.2 3.9 0
19.5
18.3
20.8
20.6
23.6
23.7
30.0
27.4
75.5
76.0
75.6
73.9
70.5
70.5
67.9
70.2
89.1 0.8 0.3 3.3 6.5
86.5 5.0 0.7 1.5 6.3
37.8 18.7 33.2 0.1 10.3
31.4 28.3 31.5 0 8.9
4.3 21.8 64.5 1.9 7.6
3.2 23.4 63.8 2.6 6.9
0.3 82.3 0.0 0.2 17.1
0.0 84.1 0.0 0.1 15.7
Katherine Pérez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series análisis. BWHO. 2009
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Figure 1. Number of motorcyclists injured and number of new registrations of light and heavy motorcycles. Barcelona, January 2002 to April 2008.
50
100
150 200
250
Number of people injured as occupants of motorcycles 50-125cc
2002
2003
2004
2005 Year
2006
2007
0
1000
2000
3000
Number of new registrations of motorcycles of 50-125cc
2002
2003
2004
2005 Year
2006
2007
50
100 150 200 250
Number of people injured as occupants of motorcycles >125cc
2002
2003
2004
2005 Year
2006
2007
0
1000
2000
3000
Number of new registrations of motorcycles >125cc
2002
2003
2004
2005 Year
2006
2007
Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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Figure 2. Observed and expected road injured among light and heavy motorcyclists users by month. Barcelona, January 2002 to April 2008. (Time series analysis with Poisson regression models, adjusted for trend and seasonality).
50
100
150
200
250
Light motorcycles (51 a 125cc)
n=1,207
n=1,280
n=1,553
n=1,809
n=2,179
n=718
Heavy motorcycles (>125cc)
50
100
150
200
250
n=1,338
n=1,179
n=1,078
n=1,209
Observed road injured
n=1,379
n=1,480
n=1,531
Expected road injured
n=503 95%CI
* Includes until April 30th 2008
Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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Figure 3. Observed and expected road injured among moped and car users by month. Barcelona, January 2002 to April 2008. (Time series analysis with Poisson regression models, adjusted for trend and seasonality).
50
100
150
200
250
Moped (<=50cc)
n=2,666
n=2,619
n=2,382
n=2,201
n=1,979
n=2,068
n=652
n=3,289
n=3,081
n=848
50
150
250
350
450
Car
n=4,610
n=4,266
n=3,897
Observed road injured
n=3,760
Expected road injured
95%CI
* Includes until April 30th 2008
Katherine PĂŠrez, et al. Impact of relaxing licensing requirements for motorcycle driving on traffic injuries: a time series anĂĄlisis. BWHO. 2009
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