Factors affecting the likelihood of reporting road crashes resulting in medical treatment to the police.

OBJECTIVE This paper aims to determine the percentage of road crashes resulting in injuries requiring hospital care that are reported to the police and to identify factors associated with reporting such crashes to the police. DESIGN The data of one of two hospitals in the Road Casualty Information System were matched with the police's Traffic Accident Database System. Factors affecting the police-reporting rate were examined at two levels: the different reporting rates among subgroups examined and tested with chi2 tests; and multiple explanatory factors were scrutinised with a logistic regression model to arrive at the odds ratios to reflect the probability of police-reporting among subgroups. RESULTS The police-reporting rate was estimated to be 57.5-59.9%. In particular, under-reporting among children (reporting rate = 33.6%) and cyclists (reporting rate = 33.0%) was notable. DISCUSSION Accurate and reliable road crash data are essential for unveiling the full-scale and nature of the road safety problem. The police crash database needs to be supplemented by other data. In particular, any estimation about the social costs of road crashes must recognise the under-reporting problem. The large number of injuries not reflected in the police crash database represents a major public health issue that should be carefully examined.