Whiplash injuries from car accidents in a Swedish middle-sized town during 1993-95

Objective - To assess the incidence of whiplash associated disorders (WAD) after minor whiplash injuries in car accidents. Design - A cohort defined by means of a health-care-based registration of traffic injuries and followed up by postal questionnaire after 12 months. Setting - Primary and hospital care in a Swedish middle-sized town (approx. 80000 inhabitants) during 2 years in the period 1993-1995. Main outcome measures - Incidence of WAD, duration of symptoms and sick leave. Results - A total of 485 injured car occupants were identified; 158 had a WAD with no difference between the sexes. The incidence was estimated to be 1/1000 inhabitants and year. The response rate to the questionnaire was 79% (125/158). In 64 cases, symptoms lasted 6 weeks and in 30 cases more than 6 months. Forty individuals (32%) reported sick leave exceeding 4 weeks in 15 cases. Seven persons (5.6%) were still on sick leave at follow-up. The duration of symptoms and sick leave was similar for men and women. Conclusion - Relatively few cases of WAD reported long-term sick leave. More cases reported chronic symptoms.