A patient's chances of undergoing surgery often depends more on where he or she lives than on their clinical circumstances, according to a two-part series exploring variation in surgery use published in the September 28 issue of The Lancet. University of Michigan Health System surgeon John D. Birkmeyer, M.D., and colleagues suggest regional variation in the use of surgical procedures exists in many different countries, yet patient demand and differences in diagnostic practices do not appear to have much of an effect on these differences. Instead, the research team said the motivations and beliefs of doctors are the most important reasons for surgical variation. Reducing variation will require systematic efforts to ensure treatment decisions are driven by the well-informed preferences of individual patients. Abstract