Screening for yellow flags in first-time acute low back pain: reliability and validity of a Norwegian version of the Acute Low Back Pain Screening Questionnaire.

OBJECTIVES: The purpose of this study was to evaluate the reliability and construct and predictive validity of the Norwegian version of the Acute Low Back Pain Screening Questionnnaire (ALBPSQ).
METHODS: A prospective study with a 12-month follow-up was conducted on 123 patients with acute low back pain (LBP) seeking help in primary health care for the first time and 50 patients with chronic LBP for more than 3 months.
RESULTS: Test-retest reliability was high with intraclass correlation coefficients of 0.90, minimal detectable change of 12 points (of a total score of 210), and coefficient of variation of 4%. Internal consistency was 0.95. Principal-components analysis revealed 3 factors explaining 49% of the variance. The ALBPSQ score correlated highly (r> or =0.60) with disability variables, moderately (0.30<r<0.60) with age, pain intensity, and psychologic, questionnaires, and weakly (r< or =0.30) with most sociodemographic and clinical variables. The ALBPSQ were significantly lower in acute compared with chronic LBP at all follow-up visits (P<0.001). Significant associations were found between high-risk and low-risk subgroups on the ALBPSQ and pain and disability variables during follow-up. Different cut-off points on the accuracy of predicting outcomes at 6 and 12 months' follow-up showed high specificity and low sensitivity with a best cut-off of 90 points. DISCUSSION: The findings of this study provide further evidence of the utility of the ALBPSQ in clinical studies and in primary care settings (general practitioners, chiropractors, and physiotherapists) to help identify patients at risk of developing chronic LBP and disability.