Validity and reliability of the Fear-Avoidance Beliefs Questionnaire (FABQ) in workers with upper extremity injuries

Introduction Fear Avoidance Beliefs (FAB) have been associated with increased pain, dysfunction and difficulty returning to work in Upper Extremity (UE) injures. The FABQ is used to assess FAB, but its measurement properties have not been established in UE. The purpose of this study is to evaluate the reliability and validity of the FABQ to screen UE compensated injured workers for FAB. Methods Consenting workers attending a specialty clinic completed a modified FABQ, QuickDASH (Disability), SPADI Pain Score and von Korff Chronic Pain Grade (Pain), SF-36v2 (General Health), and Work Instability Scale (Job Instability). A sub-sample of workers (n = 48) completed the FABQ 2 weeks later for test-retest reliability. Results 187 workers; 54.0% male; mean age 45.2 (sd 9.68); 56% were currently working. Mean subscale scores (FABQ-Work [FABQ-W]/FABQ-Physical Activity [FABQ-PA]) were 35/42 and 20/24. Ceiling effects (23%/38%) existed in both subscales. Cronbach's alphas were 0.75/0.78. Test-retest analysis (ICC(2,1)) was lower than desired (0.52/0.59). Construct validation was supported by a moderate correlation between FABQ-W/FABQ-PA and QuickDASH Work Module (0.51/0.42) and WIS (0.46/0.38) in those currently working. Low correlations were found between the subscales measures of pain (SPADI: 0.24/0.23; Chronic Pain Grade: 0.25/0.25), and SF-36 MCS (-0.25/-0.30). Conclusions Although FAB is an important concept to measure in compensated UE injured workers, the FABQ had limitations in this population as there was a high ceiling effect, and lower than desired reliability for individual discrimination. A priori hypotheses around construct validity were rejected for 16/22 concepts tested