The Degree of Shoulder Involvement in Sports (DOSIS) scale is a valid and responsive instrumentation for shoulder assessment in patients after surgery for anterior instability.

PURPOSE: The purpose of this study was to evaluate validity and responsiveness of the Degree of Shoulder Involvement in Sport (DOSIS) scale.

METHODS: A web-based survey was developed to test the construct validity of the DOSIS scale. Fifty-three patients with a median age of 33 years (range 17-59) were included in the study. Convergent validity was evaluated by external correlation (Spearman's rank correlation coefficient, r) of the DOSIS with the Brophy-Marx and Tegner activity scales, the Western Ontario shoulder instability index (WOSI), the Simple Shoulder Test (SST), and the Short-Form 36 (SF-36). Responsiveness was analysed by relative efficiency calculation of the DOSIS versus the Brophy-Marx and Tegner activity scales.

RESULTS: The DOSIS showed strong correlation with the Brophy-Marx and Tegner activity scales, a moderate correlation with the WOSI and SST scores, and a moderate correlation with the physical functioning, role physical and role emotional subscores of the SF-36. The distribution of the DOSIS scores had no serious ceiling or floor effects. The DOSIS demonstrated lesser responsiveness when compared to the Brophy-Marx and Tegner activity scales.

CONCLUSION: The DOSIS showed an adequate validity and responsiveness. The clinical relevance of this study is that the DOSIS scale can be used for sport-specific shoulder assessment in patients after surgery for anterior instability.

LEVEL OF EVIDENCE: III.