Construct and predictive validity of the German Örebro questionnaire short form for psychosocial risk factor screening of patients with low back pain.

PURPOSE

Recognizing patients at risk of developing chronic low back pain is essential for targeted interventions. One of the best researched screening instruments for this purpose is the Örebro Musculoskeletal Pain Questionnaire (ÖMSPQ). This work addresses psychometric properties of the German ÖMSPQ short form and its construct and prognostic validity.

METHODS

Analyses are based on a cluster-randomized trial assessing a risk tailored intervention for patients consulting for low back pain in 35 general practices. A total of 360 patients consulting for acute and sub-acute back pain, aged 20-60 years, were included. All patients received a 10-item German short version of the ÖMSPQ, and other generic instruments (Graded Chronic Pain Scale, Patient Health Questionnaire-Depression, Hannover Functional Ability Questionnaire, Fear-Avoidance Beliefs Questionnaire). The construct validity was assessed based on the factorial structure of the items and correlations with generic instruments. The area under the curve (AUC), sensitivity and specificity were calculated as measures of prognostic validity.

RESULTS

ÖMSPQ items belonging to the same subscale correlated highest among each other. The internal consistency of the ÖMSPQ items was 0.80 (Cronbach's α). The factorial structure corresponds with theoretic expectations. ÖMSPQ subscales on pain related disability, depression, and fear-avoidance beliefs correlated highest with their counterpart generic scales. The AUC for three ÖMSPQ-based prediction models ranged from 0.77 to 0.81.

CONCLUSIONS

Our results support a satisfactory factorial and prognostic validity of the German short ÖMSPQ. The instrument may guide the provision of targeted interventions. Further research should link it to targeted treatments.