Factors affecting employment after whiplash injury.

Of 586 employed patients with a whiplash injury 40 (7%) did not return to work. The risk was increased by three times in heavy manual workers, two and a half times in patients with prior psychological symptoms and doubled for each increase of grade of disability. The length of time off work doubled in patients with a psychological history and trebled for each increase in grade of disability. The self-employed were half as likely to take time off work, but recovered significantly more slowly than employees.