Abstract
Introduction: Clinical follow-up studies are sample based, in contrast to arthroplasty register data, which refer to the entire population treated. Aim of this study is to assess the differences in revision rate to quantify bias-factors in published literature.
Materials and Methods: A structured literature review of Medline-listed peer reviewed journals on examples has been performed concerning implants with sufficient material in both data sources available. Products with inferior outcome were subsumed in a subgroup.
Results: The number of cases presented in peer reviewed journals are relatively low in general and show a high variability.
The average revision rate in peer reviewed literature is significantly lower than in arthroplasty register data-sets.
Studies published by the inventor of an implant tend to show superior outcome compared to independent publications and Arthroplasty Register data. Factors of 4 to more than 10 have been found, which has a significant impact for the results of Metaanalyses.
When an implant is taken from the market or replaced by a successor there is a significant decrease in publications, which limits the detection of failure mechanisms such as PE wear or insufficient locking mechanisms.
The final statement made about the product under investigation seem to follow a certain mainstream.
Discussion and Conclusion: Arthroplasty Register datasets are superior to Metaanalyses of peer reviewed literature concerning revision rate and the detection of failure mechanisms. Combined reviews could reduce bias factors and thereby raise the quality of reports.
Correspondence should be addressed to: EFORT Central Office, Technoparkstrasse 1, CH – 8005 Zürich, Switzerland. Email: office@efort.org
