Fear of Movement in People With CRPS

BACKGROUND: People with complex regional pain syndrome (CRPS) commonly report a fear of movement that can worsen symptoms and increase disability. The Tampa Scale of Kinesiophobia (TSK) is used to evaluate fear of movement and (re)injury, but findings have been inconsistent in different populations. OBJECTIVE: To evaluate the psychometric properties of the Persian version of TSK-11 in individuals with upper limb CRPS. Specifically, to determine whether the factor structure aligns with the original 2-factor model, consisting of "activity avoidance" and "somatic focus." MATERIALS AND METHODS: People with CRPS (n=142, mean age=42, 54% female) completed the TSK. The psychometric testing included internal consistency, test-retest reliability (intraclass correlation coefficient), and convergent construct validity. Confirmatory and exploratory factor analyses were performed to evaluate the structural validity. RESULTS: The TSK-11 showed acceptable internal consistency (Cronbach alpha 0.93) and excellent test-retest reliability (intraclass correlation coefficient=0.93, 95% CI: 0.92-0.94). The Standard Error of Measurement and Minimal Detectable Change were 4.3 and 11.7, respectively. The results also demonstrated excellent criterion validity ( r =0.81). Confirmatory factor analysis demonstrated that the original 2-factor model did not fit. Exploratory factor analysis derived a 2-factor solution with different items. The factor structure accounted for 64.91% of the variance, and the internal consistency of the factors was acceptable (>0.90). Expert consensus suggested naming these 2 factors as fear avoidance and magnification and helplessness. DISCUSSION: The TSK-11 demonstrates excellent retest reliability in people with CRPS. The original 2-factor structure was not confirmed, and a new 2-factor structure of the TSK-11 was proposed consisting of subscales for Fear Avoidance Beliefs and Magnification/Helplessness. Given the overlap between these constructs and the construct of pain catastrophizing, further study is needed to clarify both measures' content validity and relative uniqueness.