Reliability of Pathologic Anterior Instability Presence on Shoulder Imaging—Methodological Issues: Response

Authors’ Response:

We appreciate Dr. Sabour’s helpful comments and the opportunity to clarify our findings. Dr. Sabour is correct that there are known limitations to the kappa statistic and that a weighted kappa is an appropriate test for ordinal variables for reliability assessment. We did utilize the weighted kappa for intrarater reliability of variables, which were ordinal in our manuscript. This included glenoid lesion surface area and Hill-Sachs surface area. For interrater reliability, we utilized the Kendall coefficient of concordance to describe interrater reliability for those same variables. However, this was inadvertently not indicated in our article. We hope that this response has improved the interpretation of our findings.

Charles L. Cox, MD, MPH Nashville, Tennessee, USA Natalia Glass, PhD, MHCDS Iowa City, Iowa, USA