Psychometric properties of the Fear-Avoidance Beliefs Questionnaire in patients with neck pain

OBJECTIVES: To translate the Fear-Avoidance Beliefs Questionnaire and investigate the validity and reliability of the Chinese version of the questionnaire in patients with neck pain. DESIGN: Observational cross-sectional and prospective study. SETTING: Physiotherapy outpatient departments. SUBJECTS: Four samples with 476 consecutive adult patients with neck pain from four physiotherapy centres. METHODS: The original questionnaire was translated into Chinese by forward and backward translation and reviewed by a panel of experts. The subjects completed the Chinese version of the fear-avoidance questionnaire, Northwick Park Neck Pain Questionnaire, Medical Outcomes 36-Item Short-Form Health Survey and their pain intensity was measured using an 11-point pain numerical rating scale. They were observed and measured at the beginning of physiotherapy, at week 3 and at week 6 after treatment began. RESULTS: The questionnaire had very good content validity and test-retest reliability with an intraclass correlation coefficient of 0.81 and Cronbach's alpha coefficient of 0.90. Spearman's correlation coefficients between fear-avoidance and the neck pain questionnaire, the health survey (physical), health survey (mental) and pain scale were 0.56, 0.45, 0.36 and 0.34, respectively. The standard response mean and effect size at week 6 were 0.38 and 0.32, respectively. Factor analysis yielded three factors which accounted for 61.6% of the total variance of the questionnaire. CONCLUSION: The Fear-Avoidance Beliefs Questionnaire is a valid and reliable tool for patients with neck pain. It has been shown to demonstrate very good content validity, a high degree of test-retest reliability and internal consistency, good construct validity and medium responsiveness.