Are the findings in the Swedish National Total Hip Arthroplasty Register valid? A comparison between the Swedish National Total Hip Arthroplasty Register, the National Discharge Register and the National Death Register

The Swedish National Total Kip Arthroplasty (THA) Register was initiated in 1979, and it is one of the oldest quality registers in the world. The regi ster covers all hospitals in Sweden, and today it contains >205,000 hip art hroplasties. The failure endpoint definition in the register is revision. T here is no information about quality of life and mortality. The aim of this study was to validate the results presented by the Swedish THA register by comparison with the Discharge register (the Swedish National Board of Heal th and Welfare) and to study mortality after hip arthroplasties. All hip ar throplasties from the Discharge register, performed in 1986 and thereafter, were compared with the Swedish THA register. Epidemiologic parameters, inc luding mortality, were documented from the Swedish Death register. The mort ality for primary THAs for men was 1% higher and for women 6% higher when c ompared with an age-matched and sex-matched cohort. For revision, the numbe rs were 7% and 9% higher. The risk for death compared with an age-matched a nd sex-matched population was lower for patients with osteoarthrosis treate d with hip arthroplasty. The results with revision as failure endpoint show ed that the Swedish THA register is reliable. The register includes >95% of the primary and revision THAs performed in Sweden between 1986 and 1995.