Background
Administrative claims in total joint arthroplasty are used for observational studies and payment adjustments under the Comprehensive Care for Joint Replacement (CJR) legislation. Claims data have not been validated against prospective surgical outcome registries for primary total hip (THA) or knee arthroplasty (TKA). We hypothesized that significant differences in reported comorbidity and adverse event measures exist between administrative claims and prospective registry data relevant to payment adjudication under the CJR reimbursement model.