Psychometric properties of the Thai version of the Simple Knee Value in patients with patellofemoral pain

Abstract

Purpose: This study aimed to translate the Simple Knee Value (SKV) into Thai and evaluate its psychometric properties as a single-question assessment tool. Methods: The SKV was translated into Thai according to international guidelines. Psychometric properties were assessed in adults aged 18–50 years with patellofemoral pain. Participants completed questionnaires at baseline, 2 weeks, and 2 months. Results: Seventy-six patients with patellofemoral pain (mean age 36.8 ± 8.3 years, 56.6% female) participated in this prospective cohort study. SKV scores were moderately correlated with those of the Knee Injury and Osteoarthritis Outcome Score–Patellofemoral Subscale (KOOS-PF) and the Anterior Knee Pain Scale (AKPS). The test-retest reliability was high, with an intraclass correlation coefficient of 0.79 (95% confidence interval: 0.65–0.88). The SKV change scores effectively differentiated between improved and unimproved patients, with a minimal important change of 12.5 points. Conclusions: The SKV demonstrated acceptable psychometric properties for assessing patellofemoral pain in young to middle-aged adults. This single-question patient-reported outcome measure is simple and easy to use in daily clinical practice and can serve as an adjunctive assessment tool in patellofemoral pain research.