The 20-item version of the General Health Questionnaire (GHQ) was given to 110 accidentally injured adults during the hospital stay. The patients were asked to rate their mental state prior to the accident. They also filled in the GHQ twice during a follow-up period of 28 months. All patients were twice examined by a psychiatrist who was blind to the patients' GHQ response. The overall values for sensitivity and specificity were good during the follow-up period and only slightly better using Chronic scoring procedure (80%-80%). The optimal cutting point for case screening varied across the different time-periods (2/3 pre-accident, 3/4 follow-up). Patients with permanently higher case-scores at follow-up than at pre-accident were among those severely affected by the injuries from a psychosocial point of view. The nine subjects who scored as a case at each of the three points of time all qualified for a DSM-III diagnosis. Sixty-three percent of the patients with a case score on two occasions qualified for a DSM-III diagnosis. The study indicates that GHQ-20 would be a useful measure of the psychosocial state of trauma patients seen in the course of rehabilitation.