This is a study protocol for an observational registry study on survival of ceramic vs. metal femoral heads in total primary hip arthroplasty. The protocol is based on the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines (Chan et al., 2013). The structure of the protocol is amended for an observational study. Given the availability of the data during the writing of the protocol, we detail which methods are used to attain covariate balance (Cafri and Paxton, 2018). The outcome analysis is undertaken only after finalizing the protocol
May 29, 2020