Responsiveness and Minimal Clinically Importance Difference of Thai QuickDASH in Individuals with Adhesive Capsulitis

Abstract

Objective: To explore consistency between clinical outcomes derived from patient self-assessment and physical therapy evaluation. Also, to determine the minimal clinically importance difference (MCID), responsiveness, and optimal cut-off point specific to adhesive capsulitis for conditions of high and low disability, using the Thai version of QuickDASH. Methods: A cohort study was conducted in two hospitals over six weeks of physical therapy. Eighty-seven adhesive capsulitis patients participated in this study. Clinical outcomes provided by participant self-assessment using Thai QuickDASH and Global Rating of Change (GRoC) scales were compared with irritability outcomes provided by a physical therapist. Thai QuickDASH is the validated outcomes measurement tool for adhesive capsulitis and GRoC is recommended as a standard external anchor. This anchor-based method and receiver-operating characteristics (ROC) were analysed to clarify MCID and responsiveness. Results: The highest correlation was between the Thai QuickDASH and pain during passive shoulder elevation (rho = 0.638). MCID scores ranged from 9.1 to 20.4. The optimal cut-off point between high and low disability was 31.8, attained by a combination of two references; one was a score of at least GRoC+1 and the other was irritability outcome defined by pain during passive shoulder elevation. Conclusion: Responsiveness and MCID measured by the Thai QuickDASH is specific to adhesive capsulitis. A combination of GRoC as a standard external anchor and irritability outcome gave a precise cut-off point for improvement. Overall management of adhesive capsulitis, including continuing evaluation, treatment justification, and decision planning, should be based on qualified confirmation of MCID and responsiveness.