Arabic Translation of the Knee Outcome Survey–Sports Activities Scale With Cross-cultural Adaptation and Validation

BACKGROUND: There are few sports-specific knee functional scales in the Arabic language. The Knee Outcome Survey–Sports Activities Scale (KOS-SAS) is a validated sports-specific patient-reported outcome measure that assesses knee function in an athletic population. PURPOSE: To provide a validated Arabic version of the KOS-SAS (KOS-SAS-Ar) while achieving cross-cultural adaptation for use in an Arabic-speaking population with sports-related knee disorders. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: There were 2 independent translators who conducted a forward translation of the KOS-SAS, followed by a backward translation by different translators. Subsequently, researchers and expert invitees judged the conceptual content and cultural adaptations of the final translation. A total of 276 patients completed the KOS-SAS-Ar as well as the International Knee Documentation Committee (IKDC) subjective assessment of knee function and a visual analog scale (VAS) for pain. Statistical analysis was performed for test-retest reliability, convergent validity, construct validity, and factor analysis. RESULTS: The test-retest reliability of the KOS-SAS-Ar was high (r = 0.9). The items of the KOS-SAS-Ar had statistically significant internal consistency, with a Cronbach alpha of .924 (P < .0001). The KOS-SAS-Ar Symptoms subscore correlated with the VAS pain score (P < .0001), and the KOS-SAS-Ar Functional Limitations subscore correlated with the IKDC subjective score (P < .0001). The construct validity of the KOS-SAS-Ar was satisfactory (Kaiser-Meyer-Olkin value = 0.868; Bartlett test: P < .0001). Factor analysis showed a statistical correlation among the 11 items of the KOS-SAS-Ar. CONCLUSION: The KOS-SAS-Ar demonstrated favorable reliability and validity, and it appears to be a suitable tool for Arabic-speaking patients with sports-related knee conditions.