Cross-Cultural Adaptation, Reliability, and Validity of the Greek Version of the Fremantle Shoulder Awareness Questionnaire (FreSHAQ-GR) in Patients with Chronic Shoulder Pain

Shoulder pain is one of the most common musculoskeletal pathologies. The association of shoulder pain with impaired proprioception and bodily self-awareness called for the cross-cultural adaptation of the Fremantle Shoulder Awareness Questionnaire (FreSHAQ) in Greek. The FreSHAQ is a relatively new self-assessment 9-item scale for impaired somatic awareness in patients with shoulder pain. The study included 100 participants (54 women) between 20 and 80 years old, with chronic shoulder pain (>3 months duration), able to comprehend and speak Greek, and recruited from three private physical therapy practices. The cross-cultural adaptation process was followed to develop the Greek version of the questionnaire (FreSHAQ-GR). Further testing for construct validity via exploratory factor analysis and correlational analysis with the Shoulder Pain and Disability Index (SPADI), the Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH), the pain catastrophizing scale (PCS), a pain intensity visual analog scale (PI-VAS) in the last week, and the demographic characteristics followed. Test–retest reliability of the FreSHAQ-GR in a sub-sample of patients (n = 25) was tested upon repeated completion of the scale after a week and examined with the intraclass correlation coefficient (ICC(2,1)), the standard error of the measurement (SEM), and the minimum detectable change (MDC) indices. The internal consistency of the scale was also assessed. The factor analysis revealed that the scale comprised one factor relevant to shoulder awareness but with fewer items (first 6 items) than the original FreSHAQ. Additionally, the FreSHAQ-GR (both versions) demonstrated statistically significant correlations (Spearman’s r) with participants’ age (r = −0.31/−0.29, p < 0.002), the PI-VAS (r = 0.54/0.52, p < 0.001), the SPADI total score and both of its subscales (r = 0.39–0.45/0.34–0.39, p < 0.001), the QuickDASH (r = 0.37/0.34, p < 0.001), and the PCS (r = 0.50/0.40, p < 0.001). The questionnaire’s internal consistency (Cronbach’s α/McDonald’s ω) was 0.833/0.827 for the 9-item and 0.871/0.867 for the 6-item FreSHAQ-GR. Test–retest reliability was excellent for both versions of the FreSHAQ-GR (ICC(2,1)(95% CI) = 0.97/0.98 (0.91–0.99/0.94–0.99), and with a low error margin (SEM = 1.31/0.94 and MDC(95%) = 3.63/2.61). Therefore, the FreSHAQ-GR (6-item version) possesses very good measurement properties and can be administered to Greek-speaking patients with chronic shoulder pain.