Emmanuelle Amoros

Bicycle helmet wearing and the risk of head, face, and neck injury: a French case–control study based on a road trauma registry

Background Previous case–control studies on bicycle helmet efficacy are mostly Anglo-Saxon, and based on data from the early 1990s when hard-shell helmets were common. Methods In France, the Rhône county (1.6 million inhabitants) is covered by a road trauma registry that includes emergency department visits, hospital admissions, and fatalities. Over the 1998–2008 period, 13 797 cyclist casualties were identified. The injuries sustained were coded using the Abbreviated Injury Scale (AIS) for injuries to the head (AIS1+ and AIS3+), face (AIS1+), or neck (AIS1+). The study uses a case–control design where the control group includes cyclists injured below the neck—that is, not injured in the region associated with the helmet. We first adjusted for age, gender, and type of crash, as in a previously published Cochrane review. Then we adjusted for injury severity based on non-head, face, or neck injury, and when relevant, for crash location: type of road, urban/rural area. Results The fully adjusted ORs of helmeted versus unhelmeted cyclists are: for AIS1+ head injuries, 0.69 (95% CI 0.59 to 0.81); for AIS3+ head injuries sustained in urban areas, 0.34 (95% CI 0.15 to 0.65), those sustained in rural areas, 0.07 (95% CI 0.02 to 0.23); for AIS1+ facial injuries, 0.72 (95% CI 0.62 to 0.83); and for AIS1+ neck injuries, 1.18 (95% CI 0.94 to 1.47). Conclusion This study confirms the protective effect for head and facial injuries, even though soft-shell helmets have now become more common. The reduction of risk is greater for serious head injuries. The study is inconclusive about the risk for neck injuries.

Actual Incidences of Road Casualties, and Their Injury Severity, Modelled from Police and Hospital Data, France

BACKGROUND Nation-wide road casualty figures usually come from police data. In France, as in many developed countries, the reporting of fatalities is almost complete but the reporting of non-fatal casualties is rather low. It is moreover strongly biased. Valid estimates are needed. METHODS Using the capture-recapture method on police data and on a road trauma registry covering a large county of 1.6 million inhabitants, we estimate police under-reporting correction factors that account for unregistered casualties. These correction factors are then applied to the nation-wide police data, with standardization on under-reporting bias factors. RESULTS In 2004, whereas the police report 108,727 non-fatally injured, the estimation yields 400,200. Over the 1996-2004 study period, the average annual estimated incidence is 871/100,000 for all injured (3.4 times the police incidence), 232/100,000 for hospitalized, 103/100,000 for seriously injured (2.2 times the police incidence) and 12.6/100,000 for casualties with long-term major impairment. The incidence of seriously injured (NISS 9+) is 11.3/100,000 for pedestrians, 9.5/100,000 for cyclists, 36.3/100,000 for motorized two-wheel users and 42.5/100,000 for car users. CONCLUSIONS The estimated incidences are much higher than the police-based ones. This changes the scale of the road injuries issue. The risk of suffering a major impairment from a road crash is equal to the risk of being killed. Motorized two-wheel users experience a large burden of traffic casualties, much larger than that indicated by police data. The approach used can be reproduced in other countries, if an additional medical registration exists.

The injury epidemiology of cyclists based on a road trauma registry.

BackgroundBicycle use has increased in some of Frances major cities, mainly as a means of transport. Bicycle crashes need to be studied, preferably by type of cycling. Here we conduct a descriptive analysis.MethodA road trauma registry has been in use in France since 1996, in a large county around Lyon (the Rhône, population 1.6 million). It covers outpatients, inpatients and fatalities. All injuries are coded using the Abbreviated Injury Scale (AIS). Proxies were used to identify three types of cycling: learning = children (0-10 years old); sports cycling = teenagers and adults injured outside towns; cycling as means of transport = teenagers and adults injured in towns. The study is based on 13,684 cyclist casualties (1996-2008).ResultsThe percentage of cyclists injured in a collision with a motor vehicle was 8% among children, 17% among teenagers and adults injured outside towns, and 31% among those injured in towns. The percentage of serious casualties (MAIS 3+) was 4.5% among children, 10.9% among adults injured outside towns and 7.2% among those injured in towns. Collisions with motor-vehicles lead to more internal injuries than bicycle-only crashes.ConclusionThe description indicates that cyclist type is associated with different crash and injury patterns. In particular, cyclists injured in towns (where cycling is increasing) are generally less severely injured than those injured outside towns for both types of crash (bicycle-only crashes and collisions with a motor vehicle). This is probably due to lower speeds in towns, for both cyclists and motor vehicles.

An international review of the frequency of single-bicycle crashes (SBCs) and their relation to bicycle modal share

Objectives To study cyclists’ share of transport modes (modal share) and single-bicycle crashes (SBCs) in different countries in order to investigate if the proportion of cyclist injuries resulting from SBCs is affected by variation in modal share. Methods A literature search identified figures (largely from western countries) on SBC casualties who are fatally injured, hospitalised or treated at an emergency department. Correlation and regression analyses were used to investigate how bicycle modal share is related to SBCs. Results On average, 17% of fatal injuries to cyclists are caused by SBCs. Different countries show a range of values between 5% and 30%. Between 60% and 95% of cyclists admitted to hospitals or treated at emergency departments are victims of SBCs. The proportion of all injured cyclists who are injured in SBCs is unrelated to the share of cycling in the modal split. The share of SBC casualties among the total number of road crash casualties increases proportionally less than the increase in bicycle modal share. Conclusions While most fatal injuries among cyclists are due to motor vehicle–bicycle crashes, most hospital admissions and emergency department attendances result from SBCs. As found in previous studies of cyclists injured in collisions, this study found that the increase in the number of SBC casualties is proportionally less than the increase in bicycle modal share.

Complaints of Poor Sleep and Risk of Traffic Accidents: A Population-Based Case-Control Study.

Introduction This study aimed to determine the sleepiness-related factors associated with road traffic accidents. Methods A population based case-control study was conducted in 2 French agglomerations. 272 road accident cases hospitalized in emergency units and 272 control drivers matched by time of day and randomly stopped by police forces were included in the study. Odds ratios were calculated for the risk of road traffic accidents. Results As expected, the main predictive factor for road traffic accidents was having a sleep episode at the wheel just before the accident (OR 9.97, CI 95%: 1.57–63.50, p<0.05). The increased risk of traffic accidents was 3.35 times higher in subjects who reported very poor quality sleep during the last 3 months (CI 95%: 1.30–8.63, p<0.05), 1.69 times higher in subjects reporting sleeping 6 hours or fewer per night during the last 3 months (CI 95%: 1.00–2.85, p<0.05), 2.02 times higher in subjects reporting symptoms of anxiety or nervousness in the previous day (CI 95%: 1.03–3.97, p<0.05), and 3.29 times higher in subjects reporting taking more than 2 medications in the last 24 h (CI 95%: 1.14–9.44, p<0.05). Chronic daytime sleepiness measured by the Epworth Sleepiness Scale, expressed heavy snoring and nocturnal leg movements did not explain traffic accidents. Conclusion Physicians should be attentive to complaints of poor sleep quality and quantity, symptoms of anxiety-nervousness and/or drug consumption in regular car drivers.

The burden of road traffic accidents in a French Departement: the description of the injuries and recent changes

BackgroundA significant reduction in road traffic accidents has been observed since prevention measures were introduced by the French public authorities in 2002. The goals of this study are to describe the burden of road traffic accidents in a French Departement, and to identify changes if any between the periods 1997-2001 and 2002-2006 on the basis of the disability adjusted life years (DALY).MethodsYears of lost life (YLL) and years lived with disability (YLD) were calculated for two periods using the mortality and incidence data in the Rhone Departement Registry of Road Traffic Accident Casualties.ResultsYLD and YLL that are related to road traffic accidents are at their maximum value between 15 and 24 years of age. For men, intracranial fractures and intracranial injuries dominate, and for women it is spinal cord injuries that account for highest rates of YLD. A reduction in the rates of YLL and YLD has been observed for both genders and all age groups between 1997-2001 and 2002-2006.ConclusionThe reduction in DALY between the two periods is explained both by the reduction in the number of fatalities and injuries but also by an increase in the age at which they occur.

Road crash fatality rates in France: a comparison of road user types, taking account of travel practices

BACKGROUND Travel practices are changing: bicycle and motorized two-wheeler (MTW) use are rising in some of Frances large cities. These are cheaper modes of transport and therefore attractive at a time of economic crisis, but they also allow their users to avoid traffic congestion. At the same time, active transport modes such as walking and cycling are encouraged because they are beneficial to health and reduce pollution. It is therefore important to find out more about the road crash risks of the different modes of transport. To do this, we need to take account of the number of individuals who use each, and, even better, their travel levels. METHOD We estimated the exposure-based fatality rates for road traffic crashes in France, on the basis of the ratio between the number of fatalities and exposure to road accident risk. Fatality data were obtained from the French national police database of road traffic casualties in the period 2007-2008. Exposure data was estimated from the latest national household travel survey (ENTD) which was conducted from April 2007 to April 2008. Three quantities of travel were computed for each mode of transport: (1) the number of trips, (2) the distance traveled and (3) the time spent traveling. Annual fatality rates were assessed by road user type, age and sex. RESULTS The overall annual fatality rates were 6.3 per 100 million trips, 5.8 per billion kilometers traveled and 0.20 per million hours spent traveling. The fatality rates differed according to road user type, age and sex. The risk of being killed was 20 to 32 times higher for motorized two-wheeler users than for car occupants. For cyclists, the risk of being killed, both on the basis of time spent traveling and the number of trips was about 1.5 times higher than for car occupants. Risk for pedestrians compared to car occupants was similar according to time spent traveling, lower according to the number of trips and higher according to the distance traveled. People from the 17-20 and 21-29 age groups and those aged 70 and over had the highest rates. Males had higher rates than females, by a factor of between 2 and 3. CONCLUSION When exposure is taken into account, the risks for motorized two-wheeler users are extremely high compared to other types of road user. This disparity can be explained by the combination of speed and a lack of protection (except for helmets). The differential is so great that prevention measures could probably not eliminate it. The question that arises is as follows: with regard to public health, should not the use of MTW, or at least of motorcycles, be deterred? The difference between the fatality risk of cyclists and of car occupants is much smaller (1.5 times higher); besides, there is much room for improvements in cyclist safety, for instance by increasing the use of helmets and conspicuity equipment. Traffic calming could also benefit cyclists, pedestrians and perhaps moped users.

Bicycle Helmet and Head, Face and Neck Injuries: A Case–Control Study Based on 12,000 Injured Cyclists from a Road Trauma Registry

Introduction Several case–control studies have assessed the effectiveness of the bicycle helmet against head and face injuries. This is the first case–control study in a non anglo-saxon setting; it is based on recent years, when foam helmets are the most common helmets. Material and Methods The study is based on a road trauma registry that covers both in and outpatients. Some 14 000 injured cyclists are included. Helmet wearing is routinely collected as part of the registry notification form. All injuries are recorded and coded with the Abbreviated Injury Scale (AIS). Cases are respectively defined as being AIS3+ head injured, AIS1+ head injured, AIS1+ face injured, AIS2+ neck injured and AIS1+ neck injured. A first analysis is similar to the analyses selected in the Cochrane review, adjusting for age, sex, motorised antagonist (yes/no). A second analysis restricts the dataset to cyclists who are at least injured in a body region other than head, face or neck (n=11 889), to sidestep the bias due to missing crash-involved but non-injured cyclists. This analysis moreover adjusts for more crash-force related variables. Results Fully adjusted OR on the restricted dataset for wearing a helmet is 0.29, 95% CI=[0.13 to 0.56] for AIS3+ head injuries, 0.75, CI=[0.62 to 0.91] for AIS1+ head injuries, 0.71, CI=[0.58 to 0.86] for AIS1+ face injuries, 1.51, CI=[0.56 to 3.82] for AIS2+ neck injuries and 1.34, CI=[1.01 to 1.77] for AIS1+ neck injuries. The Cochrane-like analyses lead to the same conclusions except for the risk of AIS1+ neck injuries. Conclusions The bicycle helmet protects against head and face injuries.

735 Mortality by unintentional injuries in Metropolitan France, 2000–2012

Background In metropolitan France (63 million inhabitants), around 25,000 people die each year as a result of unintentional injuries. Deaths from home and leisure injuries (HLI) are more frequent than from road traffic injuries (RTI), followed by occupational injuries (OI). The objective of this study was to measure and describe the epidemiological characteristics of deaths due to unintentional injuries in metropolitan France from 2000 to 2012. Methods HLI data come from death certificates, with an exhaustive collection. Causes of death are coded using the external causes of injury codes of the International Classification of Diseases, 10th revision. The results are expressed in numbers, crude death rates, and age-adjusted death rates. RTI data come from police records[...]. The estimation of the number of fatal OI was established from the data of the social insurance compensation funds for workers. Results In 2012, 21,470 deaths due to HLI occurred in France. Almost half of these deaths were due to falls, particularly frequent among the elderly. Between 2000 and 2012, a decrease of 2.2% (p < 0,001) of the annual mortality rate was registered. In 2011, RTI resulted in 3,793 deaths. Between 2001 and 2010, a very important reduction in road fatalities was noticed: - 52%, mostly the consequence of the large implementation of automated speed controls during that decade. As regards OI, the annual number of deaths is estimated at 1,557 (95% CI: 1,478–1,640) for the period 2002–2004. Conclusions Despite the decrease between 2000 and 2012, injuries remain a significant cause of death in France. Most of these deaths could be avoided with adapted prevention, regulation and policy measures.

Cyclists’ Injury Epidemiology Based on a Road Trauma Registry

Introduction Cycling is increasing in some cities. Bicycle injuries are often overlooked, partly because police crash data largely under-report them. Method A road trauma registry in a French area (Rhne county, population=1.6 Million) includes both in- and out-patients, with injuries coded with the Abbreviated Injury Scale (AIS). Over 1996–2006, 14 437 people were recorded as injured (or killed) while cycling. Type of cyclists is approximately defined by crash location and age: in or out of town, or children (0–10 years old). A multivariate logistic regression is performed to quantify risk factors of injury severity. Results Incidence peaks at 7–8 years old in females and at 12 in males; the sex-ratio (M/F) is 2.2 among injured children, 3.5 among in town injured cyclists and 5.7 among out of town. Most cyclists are injured on their own: 85% in children, 62% among in-town cyclists and 73% among out-of-town. Proportion of MAIS3+ is 4.6% in children, 7.3% among in-town and 10.6% among out-of-town. Adjusted risk factors for injury severity (Max.AIS3+) are as follows: being male, aged 45 or older, not wearing a helmet, crashing in a rural place, at night, on 90 km/h roads and colliding with a motorised vehicle. MAIS1 cyclists are mostly injured at the limbs (75% of them) and at the face (27%), MAIS2 cyclists at the upper limbs (58%) and head (22%), MAIS3 at the upper limbs (58%). Finally MAIS4+ cyclists (ie, with possibly fatal injuries) are mostly injured at the head (73%) and at the thorax (24%).