Cross-cultural adaptation and validation of the Persian version of the International Hip Outcome Tool-12 (iHOT-12-Pr) in young to middle-aged active adults with hip disorders

Abstract

To our knowledge, no validated Persian version of the 12-item International Hip Outcome Tool (iHOT-12) has been published for assessing active adults with hip disorders. This study aimed to translate, culturally adapt, and evaluate the psychometric properties of the Persian iHOT-12 (iHOT-12-Pr) in physically active Persian-speaking adults (18–60 years) with hip disorders. In this prospective methodological study, the iHOT-12 was translated according to established cross-cultural adaptation guidelines. The iHOT-12-Pr was completed by 126 active adults with hip disorders (Tegner Activity Scale ≥ 4) alongside the Hip Disability and Osteoarthritis Outcome Score (HOOS) and the 36-Item Short Form Health Survey (SF-36). Structural validity was assessed using parallel analysis and confirmatory factor analysis (CFA). Test–retest reliability was evaluated in 68 clinically stable participants after 7–10 days. Responsiveness was examined in 40 patients 3 months after hip arthroscopy or arthroplasty using the Global Rating of Change (GRC) scale. Parallel analysis and CFA supported a one-factor structure (comparative fit index = 0.994). The iHOT-12-Pr demonstrated excellent internal consistency (Cronbach’s α = 0.93) and test–retest reliability (intraclass correlation coefficient = 0.96, 95% confidence interval 0.93–0.97). The standard error of measurement was 3.56, and the minimal detectable change at the 95% confidence level was 9.88 points. Construct validity was supported by strong correlations with HOOS subscales (ρ = 0.79–0.85) and moderate-to-strong correlations with the physical domains of the SF-36 (ρ = 0.63–0.70). Responsiveness was high among improved participants (effect size = 1.59; standardized response mean = 1.63), and change scores strongly correlated with GRC scores (ρ = 0.84). The area under the receiver operating characteristic curve was 0.91, and the anchor-based minimal clinically important difference was 12.71 points. No floor or ceiling effects were observed. The iHOT-12-Pr demonstrated reliability, validity, and responsiveness in physically active Persian-speaking adults (18–60 years) with hip disorders. The established minimal clinically important difference exceeded the minimal detectable change, supporting interpretability of change scores for research and clinical follow-up in similar patient populations and settings.