Reliability of the Thai Version of Western Ontario Rotator Cuff Index

Abstract

Reliability of the Thai Version of Western Ontario Rotator Cuff Index

Mason Porramatikul MD

Sutee Thaveepunsan MD

Siri Sirimanakul MD

Pumibarn Wethpiriyakul MD

Department of Orthopaedic Surgery, Faculty of Medicine Vajira Hospital,

University of Bangkok Metropolis

Objectives: To translate the Western Ontario Rotator Cuff Index (WORC) questionnaire into Thai language and to evaluate its reliability.

Methods: This study was divided into 2 steps. The first step was the translation process of English WORC questionnaire into Thai after obtaining the permission from the Fowler Kennedy Sport Medicine Clinic. The translation process followed the guidelines for cross-cultural adaptation of self-report which included forward translation with cultural modification, back translation, and fine-tuning until similar meaning was obtained. The second step was to test the reliability of the Thai questionnaire in 50 patients who had rotator cuff disease and attended the outpatient orthopaedics clinic, Faculty of Medicine Vajira Hospital between June and December 2009. The internal validity was evaluated by Cronbach’s Alpha coefficient. Test-retest reliability was assessed by requesting the subjects to answer the Thai WORC twice with an interval of 30 minutes to 2 hours. The intraclass correlation coefficient (ICC) were reported.

Results: Mean age of the subjects was 61.0 + 10.4 years, 66% were female while 34% were male. Impingement syndrome was the most common rotator cuff disease (86%) followed by torn rotator cuff disease (14%). Thai version of WORC achieved good level of reliability, with the Cronbach’s Alpha coefficient of 0.998 and the ICC of 0.996.

Conclusion: Thai version of the WORC was a reliable measurement tool for assessing health-related quality of life in Thai patients with rotator cuff disease.

Keywords: Western Ontario Rotator Cuff Index (WORC), Thai version, rotator cuff, reliability