Background: The Western Ontario Shoulder Instability index (WOSI) is a questionnaire designed to measure health-related quality of life in patients with shoulder instability. The aim of the current study was to translate the WOSI into Hebrew and assess its psychometric properties.
Methods: The WOSI was translated into Hebrew according to World Health Organization guidelines. Twenty-five patients completed the WOSI and the Disabilities of Arm, Shoulder, and Hand (DASH) questionnaire 2 weeks and 2 months after surgical shoulder stabilization. Internal consistency (Cronbach's α), criterion validity (Pearson's correlation coefficient with DASH), responsiveness, and floor and ceiling effects were assessed.
Results: Cronbach's α was 0.88-0.95 for total WOSI (range 0.68-0.95 for different sections). Strong correlation with DASH score (r = 0.76-0.84) indicated good criterion validity. Changes between baseline and follow-up for WOSI and DASH scores were moderately correlated (r = 0.68), suggesting moderate responsiveness. Some items demonstrated floor and ceiling effects, especially at baseline, but no floor or ceiling effects were observed for total WOSI or for the WOSI sections.
Conclusions: The results of the current study demonstrate that the Hebrew version of the WOSI is a valid instrument that can be used to assess disability in patients with shoulder instability. Additional studies are warranted to assess its psychometric properties among various subpopulations.
Trial registration: The study was pre-registered at the ClinicalTrials.gov website, registration number NCT02978365 .
Keywords: Evaluation; Patient-reported outcome measures; Quality of life; Self-administered questionnaire; Shoulder instability.