A systematic review of medical practice variation in OECD countries.

BACKGROUND Major variations in medical practice have been documented internationally. Variations raise questions about the quality, equity, and efficiency of resource allocation and use, and have important implications for health care and health policy. OBJECTIVE To perform a systematic review of the peer-reviewed literature on medical practice variations in OECD countries. METHODS We searched MEDLINE to find publications on medical practice variations in OECD countries published between 2000 and 2011. We present an overview of the characteristics of published studies as well as the magnitude of variations for select high impact conditions. RESULTS A total of 836 studies were included. Consistent with the gray literature, there were large variations across regions, hospitals and physician practices for almost every condition and procedure studied. Many studies focused on high-impact conditions, but very few looked at the causes or outcomes of medical practice variations. CONCLUSION While there were an overwhelming number of publications on medical practice variations the coverage was broad and not often based on a theoretical construct. Future studies should focus on conditions and procedures that are clinically important, policy relevant, resource intensive, and have high levels of public awareness. Further study of the causes and consequences of variations is important.