Background A Parliamentary Bill of 2010/11 proposes Great Britain adopts Central European Time. One proposed benefit of bringing the UK into time-lines with other European countries is enhanced road safety via lighter evenings and darker mornings. There seems to be a concurrence of opinion that changing to CET would reduce road casualties, particularly child pedestrians and cyclists.
Methods The most comprehensive database of road accident casualties in Great Britain is compiled by the road accident statistics branch of the Department for Transport. We used the most recent road accident data from this source for six years (2003-2009). 36,774 children (pedestrians and cyclists) were reported as road accident casualties commuting to and from school between 2003-2009. Calculating the quality of light for each accident together with its year probability of light quality, allowed comparisons between expected and observed casualty incidence.
Findings (Table 1) During the commute home from school in twilight and darkness there were significantly less road casualties than expected (95% confidence); whilst during the morning commute twilight and darkness had the opposite effect, significantly increasing the total number of road accidents reported (95% confidence). Our results also indicated that serious injury or death as a result of a road accident for this cohort was unaffected by the quality of light, i.e. the level of light did not affect the incidence of seriously injured road casualties of schoolchildren.
Conclusion In the morning the dangers of reduced light quality increased the number of road accidents for children commuting to school as pedestrians and cyclists. However in the early evening, twilight or darkness was associated with a reduced number of road accidents. This “protective effect” it maybe postulated is the result of a behavioural change in the children. These findings challenge the proposed road safety benefits to schoolchildren that have been suggested for the “Daylight Saving Bill”.