Under-reporting of road traffic accidents

Many potentially reportable road accidents are not reported to the police and therefore do not appear in official statistics. The Department of Transport requires information on the total number and type of casualities occurring, together with their economic cost, so that road safety programmes can be as cost-effective as possible and road casualty reduction priorities can be correctly identified. This paper summarises the results of a variety of under-reporting studies. The factors affecting whether an accident was reported are identified and their effects discussed. Two recent postal surveys of motorcyclists and car drivers are analysed to examine the factors affecting reporting in more detail. Estimates of the total number of accidents not included in official figures for Great Britain are calculated and the national data adjusted for under-reporting. Additional casualty costs are also estimated.