Cross-cultural adaptation, reliability, and validity of the Turkish version of the Cumberland Ankle Instability Tool

Objectives: The objective of the study was to cross-culturally adapt and assess the validity and reliability of the Turkish version of the CAIT (CAIT-TR).Methods: The CAIT was translated and adapted into Turkish according to accepted cross-cultural adaptation guidelines of self-reported measures. A total of 130 individuals, including healthy participants (n = 40) and with chronic ankle instability (CAI) (n = 90), were recruited in this study. The internal consistency and test-retest reliability of the CAIT-TR were assessed using Cronbach's alpha and intraclass correlation coefficients (ICC), respectively. To assess convergent validity, hypotheses were tested regarding expected correlations between CAIT-TR, Foot and Ankle Outcome Score (FAOS) subscales, and the Visual Analogue Scale (VAS). Discriminative validity was evaluated with the hypothesis that the CAIT-TR can distinguish between subjects with and without CAI and also calculated a cut-off score for CAI. The dimensional structure of the CAIT-TR was investigated with confirmatory factor analysis. Additionally, minimal detectable change (MDC), floor/ceiling effects, and measurement error values were determined.Results: The CAIT-TR demonstrated high Internal consistency (Cronbach's alpha = 0.854) and test-retest reliability (ICC = 0.919). Regarding convergent validity, the CAIT-TR exhibited a moderate-strong correlation with both the FAOS and VAS. The confirmatory factor analysis supported the unidimensional structure of the questionnaire. The identified cut-off value for the CAIT-TR was 25, and the MDC for individual-level CAIT-TR scores was determined to be 1.87. No floor or ceiling effects were observedConclusion: The CAIT-TR is a valid and reliable questionnaire for the assessment of ankle instability within the Turkish population.