Responsiveness and disease specificity of the Western Ontario Rotator Cuff index.

The goal of this study was to determine the disease specificity and responsiveness of the Western Ontario Rotator Cuff Index (WORC). Responsiveness, two cut-off points of the minimal important change, the area under the curve, standard error of measurement, the minimal detectable change and the standardized response mean were determined. Patients undergoing a rotator cuff repair need to improve more than 35 points to be considered clinical importantly improved. The WORC is disease specific and has a high responsiveness in patients undergoing rotator cuff repair and patients with disease of the rotator cuff without rotator cuff tears.