This paper presents a study of accidents involving drivers on freeways in three states of the USA. The types, conditions, locations and severity of freeway accidents were analysed to identify any unique characteristics. Possible problem areas for elderly drivers were sought by examining: (1) pre-accident manoeuvres, such as merging and diverging; (2) locations, such as ramps and interchange areas; and (3) conditions, such as daytime versus night driving. The study used the integrated accident database files in the Highway Safety Information System (HSIS). The study's basic methodology required the investigation of various contingency tables, where differences of involvements in specific accident types and circumstances between elderly and middle-aged drivers were examined. Accidents during 1988-90 were analysed. Tables of results are given for each state for: (1) interchange accident involvements; (2) day/night accident involvements; and (3) severity of accident involvements. For one state, tables are given for accident type distribution and percentage involvement in pre-accident manoeuvres at interchange and non-interchange areas. The tables cover the age groups 30-50, 65-74 and 75+, and indicate some possible correlations with age.
Abstract