Junction road accidents during cross-flow turns: a sequence analysis of police case files

In-depth studies of behavioural factors in road accidents using conventional methods are often inconclusive and costly. In a series of studies exploring alternative approaches, 200 cross-flow junction road accidents were sampled from the files of Nottinghamshire Constabulary, UK, coded for computer analysis using a specially devised Traffic Related Action Analysis Language, and then examined using different computational and statistical techniques. For comparison, the same analyses were carried out on 100 descriptions of safe turns, and 100 descriptions of hypothetical accidents provided by experienced drivers. The present study employed a range of sequence analysis techniques to examine the patterns of events preceding accidents of different types. Differences were found between real accidents, hypothetical ones and safe turns; between accidents turning onto and off a road with the right of way; between the accidents of younger and older drivers; between accidents on minor roads and major roads; and between the accident expectations (but not the real accidents) of male and female drivers. Pairs of successive events often provided particularly good cues for discriminating accident types.