The present study aimed to establish criteria for delayed recovery after whiplash injury using a 1-year prospective cohort study. 117 whiplash patients referred from primary care and 16 whiplash patients recruited from the insurance company. At baseline all patients underwent neurological, radiological and psychosocial factors assessment and testing of personality traits, well-being, cognitive ability and cognitive functioning. According to the logistic regression in patients referred from primary care the following initial variables are in significant relationship with poor outcome at 1 year: impaired neck movement, history of pretraumatic headache, history of head trauma, higher age, initial neck pain intensity, initial headache intensity, nervousness score, neuroticism score and test score on focused attention. Employing these variables, correct prediction of outcome at 1 year was found in 88% of patients recruited from the insurance company. Authors conclude that a comprehensive assessment of whiplash patients early after trauma enables physicians to identify patients at risk of delayed recovery.