Understanding Orthopaedic Registry Studies

Orthopaedic registries are valuable for monitoring patient outcomes in real-world settings. Registries are useful for identifying procedure incidence and device utilization, evaluating outcomes, determining patients at risk for complications and reoperations, identifying devices in recall situations, assessing comparative effectiveness of procedures and devices, and providing data for research studies. In the present report, we describe how orthopaedic registries can be used to conduct research and how they compare with randomized controlled trials (RCTs) in regard to methodology. Using an example, a comparison of the performance of mobile and fixed bearings in total knee arthroplasty, we evaluate the differences between, and the similarities of, RCTs and registry cohort studies with regard to how they are conducted and how their findings are reported. Orthopaedic registry studies differ from RCTs in many ways and offer certain advantages. The strengths and limitations of registry cohort studies and RCTs must be understood to properly evaluate the literature. The health-care industry will be faced with substantially greater demand as our population ages and expands. By 2030, hip and knee arthroplasty will cost Medicare over $50 billion annually. Orthopaedic registries are one method for determining how best to utilize health-care resources while at the same time ensuring patient safety and quality of care. Orthopaedic registries can also provide a wealth of information from a research standpoint; however, it is important to recognize that orthopaedic registry studies are distinct from traditional clinical research. The purpose of the present study is to describe the role of orthopaedic registries and clinical trials in research. Specifically, we aimed to (1) describe how to present and interpret orthopaedic registry studies compared with clinical trials and (2) highlight differences, similarities, weaknesses, and strengths for registry and clinical trials research. What Is a Registry? A registry is defined as “an organized system that uses observational study methods to collect uniform data (clinical and other) to evaluate specified outcomes for a population defined Disclosure:None of the authors received payments or services, either directly or indirectly (i.e., via his or her institution), from a third party in support of any aspect of this work. None of the authors, or their institution(s), have had any financial relationship, in the thirty-six months prior to submission of this work, with any entity in the biomedical arena that could be perceived to influence or have the potential to influence what is written in this work. Also, no author has had any other relationships, or has engaged in any other activities, that could be perceived to influence or have the potential to influence what is written in this work. The complete Disclosures of Potential Conflicts of Interest submitted by authors are always provided with the online version of the article. Peer Review: This article was reviewed by the Editor-in-Chief and one Deputy Editor, and it underwent blinded review by two or more outside experts. It was also reviewed by an expert in methodology and statistics. The Deputy Editor reviewed each revision of the article, and it underwent a final review by the Editor-in-Chief prior to publication. Final corrections and clarifications occurred during one or more exchanges between the author(s) and copyeditors. e3(1) COPYRIGHT 2016 BY THE JOURNAL OF BONE AND JOINT SURGERY, INCORPORATED J Bone Joint Surg Am. 2016;98:e3(1-7) d http://dx.doi.org/10.2106/JBJS.N.01332 by a particular disease, condition, or exposure, and that serves one or more predetermined scientific, clinical, or policy purposes.” Registries focusing on implant surveillance can identify procedure incidence, implantable device utilization, and adverse events associated with these devices. Registries with patient and device information can also identify patients who are at risk for poor clinical outcomes and the interactions of patient characteristics with devices. Furthermore, registries can identify and monitor patients in a recall or advisory situation. In research, registries can offer advantages over clinical studies in some situations. While randomized controlled trials (RCTs) are considered the gold standard of research, wellconducted observational studies offer benefits to the understanding of practices, developments, and long-term effects of different types of exposures. Registries evaluate the performance of devices and techniques in a real-world environment. New technology monitoring is critical in the United States, where the Food and Drug Administration evaluates >4000 new medical devices per year. Unlike RCTs with strict inclusion criteria, registries assess outcomes in a wide range of patients and hospital settings and among many surgeons, resulting in more generalizable findings. Studies using registry data can also be lower in cost because of the existing infrastructure. Furthermore, registries are necessary when rare outcomes are evaluated and can be used when RCTs are unethical or cannot practically be carried out. They are dependent, however, on very high levels of data capture in order to provide an accurate picture of the clinical environment with which they are