National 10-year trend in road injuries involving school children on the way to and from school in Japan, 2003-2012

Reduced road injuries while commuting due to heavy snowfall and ensuing modal shifts among junior high school students in Japan

Background

Modal shifts in transport may reduce overall road injuries. Cyclist junior high school students are at a high risk of road injuries while commuting in Japan, and injuries among junior high school students could be reduced if the cyclists switch to other transport modes.

Methods

We estimated the change in the incidence of road deaths and serious injuries while commuting in months with heavy snowfall, when cyclists are likely to switch to other transport modes. Using police data on the monthly number of road injuries while commuting among junior high school students in Japan between 2004 and 2013 and corresponding population statistics and snowfall data, we calculated the monthly injury rate (number of deaths and serious injuries divided by population) at the prefecture level. We conducted Poisson regression analysis to estimate the change in the rate in months with a snowfall of ≥100 cm, compared to months without snowfall.

Results

A total of 3,164 deaths and serious injuries occurred during 2004 to 2013. The injury rate among cyclists was almost zero in months with a snowfall of ≥100 cm. That among cyclists and pedestrians in these months was reduced by 68% (95% confidence interval, 43–82%).

Conclusion

In months with heavy snowfall, road injuries while commuting were reduced due to the near-elimination of cycling injuries among junior high school students in Japan. Switching from cycling to other transport modes would reduce overall road injuries among this population, and inducing modal shifts can be an important tool for road safety.

Regional disparities in road traffic injury rates involving elementary and junior high school children while commuting among Japan's 47 prefectures between 2004 and 2013

OBJECTIVES

To investigate the extent and patterns of regional disparities of road traffic injury rates involving elementary and junior high school children while commuting among Japan's 47 prefectures.

METHODS

We conducted a cross-sectional ecological study using the national police data for 2004-2013 on the number of children who were killed or seriously injured (KSI) in traffic collisions stratified by prefecture, grade, mode of transport, and purpose of trip (commuting or non-commuting). We calculated stratified KSI rates by dividing the number of KSI cases by the corresponding number of children and presented these rates for the 47 prefectures. Also, for pedestrian elementary school children and cyclist junior high school children, we regressed the KSI rates while commuting by prefecture on the non-commuting KSI rates and the proportion of people who live in the urban, densely inhabited districts.

RESULTS

There were 6463 KSI cases while commuting. The ratios of the highest KSI rate to the lowest KSI rate among prefectures were 12, 30, and 58 for pedestrian elementary school children and pedestrian and cyclist junior high school children, respectively. The non-commuting KSI rates and the proportion of those living in densely inhabited districts were positively and inversely associated with the commuting KSI rates, respectively. The analysis of the residuals of the regression models did not identify prefectures with significantly higher or lower KSI rates while commuting than others.

CONCLUSIONS

There were large inter-prefecture disparities in the KSI rates while commuting, and the disparity was especially large among cyclist junior high school children.