Cross-cultural adaptation and validation of the Korean Toronto Extremity Salvage Score for extremity sarcoma

Abstract

A Korean version of Toronto Extremity Salvage Score (TESS), a widely used disease-specific patient-reported questionnaire for assessing physical function of sarcoma patients, has not been developed. 1) to translate and cross-culturally adapt the TESS into Korean, and 2) to examine its comprehensibility, reliability and validity. TESS was translated into Korean, then translated back into English, and reviewed by a committee to develop the consensus version of the Korean TESS. The Korean TESS was administered to 126 patients to examine its comprehensibility, reliability, and validity. Comprehensibility was high, as the patients rated questions as "easy" or "very easy" in 96% for the TESS lower extremity (LE) and in 97% for the TESS upper extremity (UE). Test-retest reliability with intraclass coefficient (0.874 for LE and 0.979 for UE) and internal consistency with Cronbach's alpha (0.978 for LE and 0.989 for UE) were excellent. Korean TESS correlated with the MSTS score (r = 0.772 for LE and r = 0.635 for UE), and physical functioning domain of EORTC-CLQ C30 (r = 0.840 for LE and r = 0.630 for UE). Our study suggests that Korean version of the TESS is a comprehensible, reliable, and valid instrument to measure patient-reported functional outcome in patients with extremity sarcoma.