Early identification of patients at risk of developing a persistent back problem: the predictive validity of the Orebro Musculoskeletal Pain Questionnaire.

OBJECTIVE: To test the predictive utility of the Orebro Musculoskeletal Pain Screening Questionnaire in identifying patients at risk for developing persistent back pain problems.
DESIGN: Prospective, where participants completed the questionnaire and their cases were followed for 6 months to assess outcome with regard to pain, function, and absenteeism due to sickness. PARTICIPANTS: One hundred seven patients, recruited from seven primary care units.
RESULTS: Discriminant analyses showed that the items on the questionnaire were significantly related to future problems. For absenteeism due to sickness, 68% of the patients were correctly classified into one of three groups, whereas an even distribution would have produced 33%. The analyses for function correctly classified 81%, and for pain 71%, into one of two groups, compared with a chance level of 50%. A total score analysis demonstrated that a cutoff score of 90 points had a sensitivity of 89% and a specificity of 65% for absenteeism due to sickness, and a sensitivity of 74% and a specificity of 79% for functional ability.
CONCLUSIONS: The results underscore that psychological variables are related to outcome 6 months later, and they replicate and extend earlier findings indicating that the Orebro Screening Questionnaire is a clinically reliable and valid instrument. The total score was a relatively good predictor of future absenteeism due to sickness as well as function, but not of pain. The results suggest that the instrument could be of value in isolating patients in need of early interventions and may promote the use of appropriate interventions for patients with psychological risk factors.