Arabic version of the international knee documentation committee subjective knee form (IKDC): Translation and validation

Abstract

BACKGROUND: In order to administer the International Knee Documentation Committee Subjective Knee Form (IKDC) questionnaire to Arabic speakers, a rigorous process of cross-cultural adaptation and validation is required in order to reach equivalence between the original publication and target version of the questionnaire. OBJECTIVES: The main aim of this study is to translate and culturally adapt the IKDC into Arabic to suit the Arabic population. The secondary aim is to assess the Arabic version of the IKDC in order to test the psychometric characteristics (reliability, validity and dimensionality). METHODS: The translation process has been carried out according to cross-cultural adaptation guidelines in accordance with the American Orthopaedic Society for Sports Medicine guidelines with forward/backward translations and pre-testing. The Arabic IKDC, Knee injury and Osteoarthritis Outcome Score (KOOS), RAND-36-Item Health Survey (RAND-36) questionnaire, and visual analogue scales (VAS) of pain were tested in 105 ACLR patients. Test-retest reliability, internal consistency, construct validity and content validity were evaluated. RESULTS: The test-retest reliability proved excellent with a high value for the intraclass correlation coefficient (r= 0.95). The internal consistency was strong (Cronbach’s α= 0.91). Good construct validity by the strong correlations between similar component of the KOOS subscales, Rand-36 subscales and VAS, and good content validity with absence of floor and ceiling effects. CONCLUSIONS: The Arabic version of the IKDC is a valid and reliable instrument for Arabic patients with ACLR. However, further research is required with a more varied knee sample in order to enable generalisation to a wider population.