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In recent years, the role of "sleepiness at the wheel" in the occurrence of accidents has been increasingly highlighted with several national and international public health campaigns based on consensual research publications. However, one aspect of this phenomenon is rarely taken into account, i.e., the risk of sleep-induced accidents while riding powered two-wheelers (PTWs). PTWs are indeed involved in a high percentage of fatal accidents mostly with young male riders. The effects of sleepiness may be different in drivers and riders, partly because riders may be stimulated more by the road environment. But riders (differently from drivers) have also to maintain continuously a balance between their own stability and the need of following the road, even when they are directly exposed to adverse climatic conditions. We, therefore, gathered the limited scientific literature on this topic and tried to analyze how riders may be affected differently by sleepiness. Finally we provide some suggestions as to how this question may be better approached in the future.

In this paper, a machine-learning framework is used for riding pattern recognition. The problem is formulated as a classification task to identify the class of riding patterns using data collected from 3-D accelerometer/gyroscope sensors mounted on motorcycles. These measurements constitute an experimental database used to analyze powered two-wheeler rider behavior. Several well-known machine-learning techniques are investigated, including the Gaussian mixture models, the $k$ -nearest neighbor model, the support vector machines, the random forests, and the hidden Markov models (HMMs), for both discrete and continuous cases. Additionally, an approach for sensor selection is proposed to identify the significant measurements for improved riding pattern recognition. The experimental study, performed on a real data set, shows the effectiveness of the proposed methodology and the effectiveness of the HMM approach in riding pattern recognition. These results encourage the development of these methodologies in the context of naturalistic riding studies.

Background: Noise in the vicinity of airports is a crucial public health issue. Exposure to aircraft noise has been shown to have adverse effects on health and particularly on sleep. Many studies support the hypothesis that noise at night can affect subjective sleep quality. Fewer studies, however, have performed objective measurements of sleep. Objectives: The aim of the present study was to investigate the relationship between aircraft noise exposure and objective parameters assessed by actigraphy of sleep quality in the population living near two French airports. Methods: This study includes 112 participants living in the vicinity of Paris-Charles de Gaulle and Toulouse-Blagnac airports. Wrist actigraphy measurements were performed during eight nights to evaluate objective parameters of sleep quality such as sleep onset latency (SOL), wake after sleep onset (WASO), total sleep time (TST), time in bed (TB) and sleep efficiency (SE). Acoustic measurements were made simultaneously both inside the participants' bedrooms and outside (at the exterior frontage) in order to estimate aircraft noise levels. Energy indicators related to the sound energetic average for a given period of time, as well as indicators related to noise events (such as the number of events that exceed a given threshold for example) were estimated. Logistic and linear regression models were used, taking into account potential confounders: age; gender; marital status; education; and body mass index (BMI). Results: Energy indicators, and more particularly indicators related to noise events, were significantly associated with objective parameters of sleep quality. Increased levels of aircraft noise and increased numbers of aircraft noise events increased the time required for sleep onset (SOL) and the total wake time after sleep onset (WASO), and decreased sleep efficiency (SE). An association was also observed between aircraft noise exposure and an increase in total sleep time (TST) and time in bed (TB). Conclusion: The findings of the present study contribute to the overall evidence suggesting that nocturnal aircraft noise exposure may decrease objective quality of sleep. Aircraft noise exposure affects objective parameters of sleep quality, not only in terms of noise levels but also in terms of number of events. Mechanisms for adapting to sleep deprivation could be observed.

Background: Exposure to aircraft noise has been shown to have adverse effects on health, particularly on sleep. Exposure to nighttime aircraft noise clearly affects sleep architecture, as well as subjective sleep quality. Objectives: This study aimed to investigate the relationship between aircraft noise exposure and subjective sleep quality in the population living near airports in France. Methods: A total of 1,244 individuals older than 18 and living near three French airports (Paris-Charles de Gaulle, Lyon-Saint-Exupery and Toulouse-Blagnac) were randomly selected to participate in the study. Information on sleep as well as health, socioeconomic and lifestyle factors was collected by means of a face-to-face questionnaire performed at their place of residence by an interviewer. For each participant, aircraft noise exposure was estimated at home using noise maps. Logistic regression models were used with adjustment for potential confounders. Results: Aircraft noise exposure was significantly associated with a short total sleep time (TST) (£ 6 h) and with the feeling of tiredness while awakening in the morning. An increase of 10 dB(A) in aircraft noise level at night was associated with an OR of 1.63 (95%CI: 1.15-2.32) for a short TST and an OR of 1.23 (95%CI: 1.00-1.54) for the feeling of tiredness while awakening in the morning. Conclusions: These findings contribute to the overall evidence suggesting that aircraft noise exposure at nighttime may decrease the subjective amount and quality of sleep.

Background Saliva cortisol is a possible marker of noise-induced stress and could then mediate the relation observed between exposure to aircraft or road traffic noise and cardiovascular diseases. However, the association between transportation noise and cortisol levels is still unclear. The objective of the study was to investigate the variability of saliva cortisol concentration as an indicator of disturbed hypothalamus-pituitary-adrenal (HPA) axis regulation in relation to long-term aircraft noise exposure. Methods Saliva samples were taken when awakening and before going to bed for 1244 participants older than 18 years of age. Information about health, socioeconomic and lifestyle factors was also collected by means of a face-to-face questionnaire performed at home by an interviewer. Aircraft noise exposure was assessed for each participant’s home address using noise maps. Linear regression models were used to evaluate the effects of aircraft noise exposure on the morning and evening cortisol levels and on the daily variation of cortisol per hour. Results This study suggests a modification of the cortisol circadian rhythm in relation to aircraft noise exposure. This exposure was associated with a smaller variation of cortisol levels over the day, with unchanged morning cortisol levels, but higher cortisol levels in the evening. Conclusions These findings provide some support for a psychological stress induced by aircraft noise exposure, resulting in HPA dysregulation and a flattened cortisol rhythm, thus contributing to cardiovascular diseases.

Objectives The largest study until now around 6 major European airports, the HYENA (HYpertension and Exposure to Noise near Airports) study, reported an excess risk of hypertension related to long-term aircraft noise exposure. The DEBATS (Discussion on the health effects of aircraft noise) study investigated the relationship between this exposure and the risk of hypertension in men and in women near French airports. Methods Blood pressure of 1244 participants older than 18 years of age was measured. Information about health, socioeconomic and lifestyle factors was collected by means of a face-to-face questionnaire performed at home by an interviewer. Aircraft noise exposure was assessed for each participant9s home address using noise maps. They were calculated with the Integrated Noise Model with a 1 dB(A)-resolution. The major potential confounders being risk factors for hypertension were included in the logistic regression models: age, occupational activity, body mass index, physical activity and alcohol consumption. Results After adjustment for the main potential confounders, an exposure–response relationship was evidenced between the risk of hypertension and aircraft noise exposure at night for men only. A 10-dB(A) increase in L night was associated with an OR of 1.34 (95% CI 1.00 to 1.97). Conclusions These findings contribute to the overall evidence suggesting that aircraft noise exposure at night-time may increase the risk of hypertension in men. Hypertension is a well-known and established risk factor for cardiovascular disease. The association reported in the present study between aircraft noise and hypertension implies that aircraft noise might be a risk factor also for cardiovascular disease.

This paper presents a naturalistic study of motorcyclists' behaviours during their commutes in the Paris region. The study focuses on lane splitting, which consists of riding between two streams of slow or stopped vehicles that are proceeding in the same direction. This practice is frequent in dense traffic on French urban expressways and particularly in the Paris region but remains without detailed scientific analysis. In an ergonomic approach, 11 motorcyclists drove for a month with an instrumented vehicle with cameras. The video recordings enabled the description of the driving contexts and the conduct of self-confrontation interviews. The results concern firstly the description of the practice of lane splitting and its significance in their daily journeys. Secondly, the findings indicate the importance of perceptual activities in the participants' riding behaviour. These perceptual activities are organized around two major processes: (1) an intensive search for information in the environment in order to foresee risky situations and (2) the detection of situations that systematically impair the visual conspicuity of the riders and taking steps to improve it. The findings are discussed with a view to gaining a better understanding of lane-splitting practices. At the time of writing, the results are also being used by the French authorities to improve the training curriculum and modify the legislation that deals with lane splitting.

International audience; This paper analyses motorcycle educational content in a number of French motorcycle schools on the basis of a naturalistic study of riders' and trainers' behaviour. The aim is to specify the situations delivered in motorcycle schools and to study the rider's activity in these situations. The methodology includes ethnographic observation within the motorcycle schools and the longitudinal monitoring of 14 trainee motorcyclists during their initial training. The training situations were described by the combination of audio-visual recordings and interviews data (i.e. concomitant or interruptive verbalization, and self-confrontation data). The results permit to (1) compare the "real" and "official" durations of track and on-road training, (2) characterize the real training situations, (3) describe the preferred forms of instruction, and (4) conduct an in-depth analysis of the situations used during training in traffic. The discussion show, in first, the poverty of the training situations which are based on the repetition of the exercises in the test, and, in second, disparities between the riding situations encountered during training and the demands made by riding in natural traffic. The usefulness and the applications of this type of approach - based on the integration of the rider's point of view notably by self-confrontation interview - for understanding real riding behaviours and how such approaches could supplement vehicle-based data are discussed in a large conclusion.

This article sets out to identify the typical risky situations experienced by novice motorcyclists in the real world just after licensing. The procedure consists of a follow-up of six novices during their first two months of riding with their own motorbike instrumented with cameras. The novices completed logbooks on a daily basis in order to identify the risky situations they encountered, and were given face-to-face interviews to identify the context and their shortcomings during the reported events. Data show a large number of road configurations considered as risky by the riders (248 occurrences), especially during the first two weeks. The results revealed that a lack of hazard perception skills contributed to the majority of these incidents. These situations were grouped together to form clusters of typical incident scenarios on the basis of their similarities. The most frequent scenario corresponds to a lane change in dense traffic (15% of all incidents). The discussion shows how this has enhanced our understanding of novice riders' behaviour and how the findings can improve training and licensing. Lastly, the main methodological limitations of the study and some guidelines for improving future naturalistic riding studies are presented. Practitioner Summary: This article aims to identify the risky situations of novice motorcyclists in real roads. Two hundred forty-eight events were recorded and 13 incident scenarios identified. Results revealed that a lack of hazard perception contributed to the majority of these events. The most frequent scenario corresponds to a lane change in dense traffic.

Objective.To compare health status, effect on family, occupational consequences, and quality of life (QOL) 1 year after an accident between patients with whiplash versus other mild injuries, and to explore the relationship between initial injury (whiplash vs other) and QOL.Methods.This was a prospective cohort study. The study used data from the ESPARR cohort (a representative cohort of road accident victims) and included 173 individuals with “pure” whiplash and 207 with other mild injuries. QOL at 1-year followup was assessed on the World Health Organization Quality of Life questionnaire. Correlations between explanatory variables and QOL were explored by Poisson regression to provide adjusted relative risks, with ANOVA for the various QOL scores explored.Results.One year post-accident, more patients who had whiplash than other casualties complained of nonrecovery of health status (56% vs 43%) and of the occupational effect of pain (31% vs 23%). QOL and posttraumatic stress disorder (PTSD) were similar in the 2 groups. Impaired QOL did not correlate with whiplash when models were adjusted on sociodemographic variables and history of psychological distress. Whatever the initial lesion, PTSD was a determining factor for poorer QOL.Conclusion.Sociodemographic factors, preaccident psychological history prior to the accident, and PTSD were the main factors influencing QOL, rather than whether the injury was whiplash. PTSD may also be related to pain.

OBJECTIVES: To identify factors associated with driving restriction in elderly men and women. DESIGN: Prospective cohort study of French drivers from 2003 to 2009. SETTING: The Three-City Cohort of Bordeaux, a prospective study of 2,104 people aged 65 and older. PARTICIPANTS: Five hundred twenty-three drivers with a mean age of 76 (273 male, 250 female). MEASUREMENTS: Sociodemographic characteristics, driving habits, health variables, cognitive evaluation and dementia diagnosis. Predementia was defined as no dementia at one follow-up and dementia at the next follow-up. RESULTS: Over the 6-year period, 54% of men and 63% of women stopped driving or reduced the distance they drove. Predementia, Parkinson's disease, older age, and a high number of kilometers previously driven were common restriction factors in both sexes. Prevalent dementia, depressive symptomatology, a decline in one or more instrumental activities of daily living, and poor visual working memory were specific factors in men. In women, low income, fear of falling, slow processing speed, and severe decline in global cognitive performance all affected driving restriction. CONCLUSION: Older women restricted their driving activity more than older men, regardless of the number of kilometers previously driven, physical health, and cognitive status. Factors affecting driving restriction differed according to sex, and women were more likely to stop driving than men in the period preceding a dementia diagnosis.

In Côte d'Ivoire alcohol and drugs consumption in the general population is a serious issue. However, their role in Road Traffic Accidents (RTAs) has never been investigated. Our study aimed to estimate the prevalence of alcohol-impaired road users at the time of the RTA and report psychoactive drug use, in various categories of casualties, and in various circumstances of the crash. We conducted a cross-sectional study including 893 casualties involved in fatal or non-fatal RTAs and admitted at the Emergency Room or the Forensic Institute from March to September 2012. Blood alcohol dosage (BAC) and urine drug screening were carried out, and results were linked with hospital and police crash report data. The mean BAC in positive cases indicated heavy drinking before the crash: drivers (1.9 g/L), pedestrians (2.1 g/L), passengers (1.5 g/L). The prevalence of alcohol-impairment was significantly higher in drivers (41%) and riders (27%) compared to pedestrians (17%) and passengers (13%). Over 75% of casualties that tested positive for alcohol had a BAC largely above the legal limit. Psychoactive drug use was twice more prevalent in alcohol-impaired drivers than in sober drivers (20% vs 10%). Binge drinking is an emerging issue in African countries, which should be taken into account in the management or prevention of road traffic injuries.

This study is concerned initial motorcycle training delivered in motorcycle schools in France. Novice motorcyclists are a particularly vulnerable group of road users in Europe and in France. However, scientific attempts to achieve a better understanding of their behaviors have been limited. The potential value of studying initial motorcycle training, both for research purposes and with regard to public policy, is readily apparent. The aims of this paper are to describe the real educational content of training in motorcycle schools and analyze to what extent this content is related to riding after licensing. A case study of all the training process of one trainee (38 hours) was carried out in real world. Audiovisual recordings and interview data of the rider and instructors were collected at each session. This study was supplemented by ethnographic observations of the educational content provided in three motorcycle schools throughout the instructors’ working days. The results that merged from both studies show (1) the riding skills that were fostered (i.e. control skills, and especially emergency skills, in stable and restricted environments) and undervalued (i.e. hazard perception skills, everyday skills) during initial training, and (2) the poverty of observed training settings: learners spend almost all their training time riding in the same setting that is used in the test. In addition to being repeated to excess, these settings are quite different from the real traffic. These results are discussed regarding the scientific literature on motorcycle education. The conclusion presents the implications of these results for public policy in order to design a future rider training system.

Background: The rapid increase in mobile telephone use has generated concern about possible health risks of radiofrequency electromagnetic fields from these devices. Methods: A case-control study of 1105 patients with newly diagnosed acoustic neuroma (vestibular schwannoma) and 2145 controls was conducted in 13 countries using a common protocol. Past mobile phone use was assessed by personal interview. In the primary analysis, exposure time was censored at one year before the reference date (date of diagnosis for cases and date of diagnosis of the matched case for controls); analyses censoring exposure at five years before the reference date were also done to allow for a possible longer latent period. Results: The odds ratio (OR) of acoustic neuroma with ever having been a regular mobile phone user was 0.85 (95% confidence interval 0.69-1.04). The OR for >= 10 years after first regular mobile phone use was 0.76 (0.52-1.11). There was no trend of increasing ORs with increasing cumulative call time or cumulative number of calls, with the lowest OR (0.48 (0.30-0.78)) observed in the 9th decile of cumulative call time. In the 10th decile (>= 1640 h) of cumulative call time, the OR was 1.32 (0.88-1.97); there were, however, implausible values of reported use in those with >= 1640 h of accumulated mobile phone use. With censoring at 5 years before the reference date the OR for >= 10 years after first regular mobile phone use was 0.83 (0.58-1.19) and for >= 1640 h of cumulative call time it was 2.79(1.51-5.16). but again with no trend in the lower nine deciles and with the lowest OR in the 9th decile. In general, ORs were not greater in subjects who reported usual phone use on the same side of the head as their tumour than in those who reported it on the opposite side, but it was greater in those in the 10th decile of cumulative hours of use. Conclusions: There was no increase in risk of acoustic neuroma with ever regular use of a mobile phone or for users who began regular use 10 years or more before the reference date. Elevated odds ratios observed at the highest level of cumulative call time could be due to chance, reporting bias or a causal effect. As acoustic neuroma is usually a slowly growing tumour, the interval between introduction of mobile phones and occurrence of the tumour might have been too short to observe an effect, if there is one. (C) 2011 Elsevier Ltd. All rights reserved.