A case-control study of child bicycle injuries: relationship of risk to exposure

A matched case-control approach to identify the risk factors of fatal pedestrian crashes on a six-lane rural highway in India

Globally, the increase in pedestrian fatalities due to road traffic crashes (RTCs) on transport networks has been a major concern. In low- and middle-income countries (LMICs), pedestrians face a high risk due to RTCs on the rural highway network. The safety evaluation methods, such as observational before-after, empirical Bayes, full Bayes, and cross-sectional methods have been used to identify risk factors of RTCs. However, these methods are data-intensive and have associated limitations. Thus, this study employed a matched case-control method to identify the risk factors of fatal pedestrian crashes. This study utilized crash, traffic volume, speed, geometric, and roadside environment data of a 175 km six-lane rural highway in India. The identified major risk factors, such as clear zone width, the presence of habitation, service roads, and horizontal curve sections, increase the likelihood of a fatal pedestrian crash. This study provides specific insights for modifying the speed limit of highway sections passing through habitation. On such highway sections, designers should shift focus to pedestrian safety. It also suggests that the service road design needs to be reconsidered from a pedestrian safety viewpoint. The proposed method can be used in any other setting having similar traffic and socio-economic conditions.

Risk Factors for Bicycling Injuries in Children and Adolescents: A Systematic Review

CONTEXT

Child and adolescent bicycling is beneficial, but injuries occur and can be severe and costly.

OBJECTIVE

To systematically review the individual and environmental factors associated with bicycling injury risk in children and adolescents.

DATA SOURCES

Fourteen electronic databases were searched.

STUDY SELECTION

Two authors independently assessed potentially relevant articles for eligibility. The inclusion criteria were as follows: bicyclists younger than 20 years old; examined individual and environmental characteristics of bicycling crashes; compared injured and uninjured bicyclists or bicyclists with different types or severity of injury; study designs with a predetermined comparison group; and published in English from January 1990 to May 2015. The exclusion criteria were outcomes related to helmet use, helmet legislation, or mountain biking, and comparisons of census-based injury rates.

DATA EXTRACTION

Data on study design, setting, population, injury definitions, injury risk factors, and results were extracted. Risk of bias was assessed by using the Newcastle-Ottawa Scales.

RESULTS

Fourteen articles were included. Lower socioeconomic status, riding on the road, riding in rural compared with urban areas, and riding on the sidewalk were associated with bicycling injury. Bicycling safety education did not protect children against future injury. Injuries related to a motor vehicle collision were more severe than other bicycling injuries.

LIMITATIONS

Study heterogeneity prevented meta-analyses. Study quality was affected by inadequate definitions of study groups and self-reported data.

CONCLUSIONS

Lower socioeconomic status and riding location were associated with bicycling injury and severity increased with motor vehicle collisions. The bicycling environment is a promising avenue for prevention.

Measurement of a drowning incidence rate combining direct observation of an exposed population with mortality statistics

Drowning risk factors may be identified by comparing drowning incidence rates for comparable at-risk populations but precise methods are lacking. To address this knowledge gap, an ecological study extrapolated crude time-duration exposure to water for a specified at-risk sample of surf bathers to estimate the bather population for all wave-dominated beaches in Victoria, Australia, over a four-year summer season period. An incidence rate was calculated using surf bather drowning deaths frequencies matched for time and location. For the sample, 47,341 hours of surf bathing were estimated from 177,528 bathing episodes. Generalising these results to Victoria, the crude drowning deaths incidence rate in the summer season was 0.41 per 1,000,000 person-hours of surf bathing (95% CI 0.37-0.45). Further application of the method, particularly in open water settings, may be used to identify candidate drowning risk factors to advance drowning prevention strategies.

Road use pattern and risk factors for non-fatal road traffic injuries among children in urban India

OBJECTIVE

We assessed the road use pattern and incidence and risk factors of non-fatal road traffic injuries (RTI) among children aged 5–14 years in Hyderabad, India.

METHODS

In a cross-sectional population-based survey, data were collected on 2809 participants aged 5–14 years (98.4% participation) selected using multi-stage cluster sampling. Participants recalled non-fatal RTI during the previous 3 and 12 months. RTI was defined as an injury resulting from a road traffic crash irrespective of severity and outcome.

RESULTS

Boys (11.5) had a higher mean number of road trips per day than girls (9.6), and the latter were more likely to walk and less likely to use a cycle (p < 0.001). With increasing household income quartile,the proportion of trips using cycles or motorised two-wheeled vehicles increased while trips as pedestrians decreased (p < 0.001). Based on the 3-month recall period, the age-sex-adjusted annual rate of RTI requiring recovery period of >7 days was 5.8% (95% CI 4.9–6.6). Boys and girls had similar RTI rates as pedestrians but boys had a three times higher rate as cyclists. Considering the most recent RTI in the last 12 months, children of the highest household income quartile were significantly less likely to sustain pedestrian RTI (0.26, 95% CI 0.08–0.86). The odds of overall RTI were significantly higher for those who rode a cycle (2.45, 95% CI 1.75–3.42) and who currently drove a motorised two-wheeled vehicle (2.83,95% CI 1.60–5.00).

CONCLUSION

These findings can assist in planning appropriate road safety initiatives to reduce cycle and pedestrian RTI among children to reduce RTI burden in India.

A mixed generalized ordered response model for examining pedestrian and bicyclist injury severity level in traffic crashes

This paper proposes an econometric structure for injury severity analysis at the level of individual accidents that recognizes the ordinal nature of the categories in which injury severity are recorded, while also allowing flexibility in capturing the effects of explanatory variables on each ordinal category and allowing heterogeneity in the effects of contributing factors due to the moderating influence of unobserved factors. The model developed here, referred to as the mixed generalized ordered response logit (MGORL) model, generalizes the standard ordered response models used in the extant literature for injury severity analysis. To our knowledge, this is the first such formulation to be proposed and applied in the econometric literature in general, and in the safety analysis literature in particular. The MGORL model is applied to examine non-motorist injury severity in accidents in the USA, using the 2004 General Estimates System (GES) database. The empirical findings emphasize the inconsistent results obtained from the standard ordered response model. An important policy result from our analysis is that the general pattern and relative magnitude of elasticity effects of injury severity determinants are similar for pedestrians and bicyclists. The analysis also suggests that the most important variables influencing non-motorist injury severity are the age of the individual (the elderly are more injury-prone), the speed limit on the roadway (higher speed limits lead to higher injury severity levels), location of crashes (those at signalized intersections are less severe than those elsewhere), and time-of-day (darker periods lead to higher injury severity).

Risk factors in highway traffic accidents: a case control study

The objective of this study was to identify risk factors related to the driver, the vehicle and the environment, that are associated with motor vehicles accidents on highways. A case and control design was used where the case was: the driver of a motor vehicle who was involved in an accident while traveling on the Mexico-Cuernavaca highway; and the control was: the driver or a motor vehicle who, traveling on the highway, completed the trip without being involved in a traffic accident. Risk factors associated with the occurrence of a traffic accident (P > 0.05) were: age under 25 years, frequent travel, traveling to work, alcohol consumption, driving during the daylight, on a week-day, under adverse weather conditions and in the Mexico Cuernavaca direction of road. Risks adjusted by logistic regression were: age under 25 years odds ratio (OR) 3.01, confidence interval (CI) (95%) 1.46-6.18; work as a travel reason OR 1.74, CI 1.06 2.86; alcohol intake OR 4.70, Cl 1.62 13.6; driving under adverse weather conditions OR 5.70, CI 3.66-8.85; traveling on a week-day OR 1.84, CI 1.14-2.94; during daylight hours OR 4.23, CI 2.36-7.58 and in the Mexico Cuernavaca direction of road OR 2.69, CI 1.67 4.32. The identification of factors associated with the risk of being involved in a highway traffic accident allows us to propose primary prevention measures for this important public health problem.

Attention and expectation problems in bicycle-car collisions: an in-depth study

One hundred and eighty-eight bicycle-car accidents in four cities were studied by multidisciplinary in-depth analysis. The sample was representative of the national accident statistics. All the accidents were analyzed in detail to reconstruct the actual movements of those involved and to assess detection of the other party. In 37% of collisions, neither driver nor cyclist realized the danger or had time to yield. In the remaining collisions, the driver (27%), the cyclist (24%) or both (12%) did something to avert the accident. Two common mechanisms underlying the accidents were identified. First, allocation of attention such that others were not detected, and second, unjustified expectations about the behavior of others. These mechanisms were found to be closely related to the system of two-way cycle tracks and to the fact that the general priority rule is applied to the crossings of a cycle track and a roadway. The most frequent accident type among collisions between cyclists and cars at bicycle crossings was a driver turning right and a bicycle coming from the driver's right along a cycle track. The result confirmed an earlier finding (Accident Analysis and Prevention 28, 147-153, 1996) that drivers turning right hit cyclists because they looked left for cars during the critical phase. Only 11% of drivers noticed the cyclist before impact. Cyclists' behavior was in marked contrast to that of drivers. In these cases, 68% of cyclists noticed the driver before the accident, and 92% of those who noticed believed the driver would give way as required by law. Cyclists with a driving license and those who cycled daily through the accident site were involved in different accident types to other cyclists.

School based bicycle safety education and bicycle injuries in children: a case-control study

OBJECTIVES

To evaluate possible benefits of a school based bicycle safety education program ("Bike Ed") on the risk of bicycle injury in children.

METHODS

A population based case-control study was undertaken in a region of Melbourne, Australia. Cases were children presenting at hospital emergency departments with injuries received while riding bicycles. Controls were recruited by calling randomly selected telephone numbers. Data were collected by personal interview.

RESULTS

Analysis, based on 148 cases and 130 controls aged 9 to 14 years, showed no evidence of a protective effect and suggested a possible harmful effect of exposure to the bicycle safety course (odds ratio (OR) 1.64, 95% confidence interval (CI) 0.98 to 2.75). This association was not substantially altered by adjustment for sex, age, socioeconomic status, and exposure, measured as time or distance travelled. Subgroup analysis indicated that the association was strongest in boys (OR 2.0, 95% CI 1.1 to 3.8), younger children, children from families with lower parental education levels, and children lacking other family members who bicycle.

CONCLUSIONS

It is concluded that this educational intervention does not reduce the risk of bicycle injury in children and may possibly produce harmful effects in some children, perhaps due to inadvertent encouragement of risk taking or of bicycling with inadequate supervision.

Walking to school and traffic exposure in Australian children

Daily patterns of pedestrian activity in young children have important health implications, primarily because of the risk of road traffic injury, but also because they may reflect the commencement of exercise habits with long-term consequences. A cross-sectional survey in two Australian cities, Melbourne and Perth, aimed to collect, by parent self-administered questionnaire, population-based data on modes of travel, numbers of street crossings (both accompanied and unaccompanied by an adult), and sociodemographic factors for six- and nine-year-old children. Results indicate that 35 per cent (95 per cent confidence interval (CI) 31 to 39 per cent) and 31 per cent (CI 28 to 34 per cent) walk to school in Melbourne and Perth respectively, while over 60 per cent are driven to school by car, with very small proportions riding bicycles or taking public transport. A higher level of walking was associated with lower levels of several indicators of socioeconomic status. Logistic regression analysis showed that the strongest predictor of walking activity was school type (government versus independent), and after adjusting for this, lesser car ownership, non-English-speaking background and lower occupational category were associated with walking to school, while a different set of predictors--age, sex and maternal education--was associated with the unaccompanied crossing of streets. There was little difference in overall walking levels between boys and girls, but boys were significantly more likely to cross streets unaccompanied (adjusted odds ratio 1.41, CI 1.14 to 1.72), providing a partial explanation of documented sex differences in injury rates.