Objectives - To evaluate pain, cervical range of motion (CROM) and cognitive symptoms as predictors for poor prognosis defined as sick leave 3 years later. Material and methods - In 97 patients CROM, pain intensity and cognitive symptoms were measured immediately following trauma, at 6 months and 3 years. Patients were also asked at 3 years if they had been on sick leave the last 6 months. Results - Pain intensity and reduced CROM were not clinically useful as predictors of later sick leave. The best predictors were presence within 96 h after injury of the two cognitive symptoms 'being easily distracted' (odds ratio 8.7-50) and 'easily irritated' (odds ratio 5.3-31). Conclusions - Initial pain and reduced CROM may be related to minor tissue damage which often heals while late functionality is more dependent on other factors such as cognitive dysfunction. For patients with whiplash-associated disorders two simple questions should be asked; 'Are you currently easily irritated?' and 'Are you currently easily distracted (e.g. is it difficult for you to follow a conversation if several people are talking in the room at the same time)?'. An affirmative answer to any of these questions indicates an increased risk for poor prognosis defined as sick leave 3 years later. © 2009 Blackwell Munksgaard.