It is widely recognized that health care spending varies noticeably across the United States - averaging less than $5000 per year for each Medicare beneficiary in Portland, Oregon, and over $10,000 in Miami, Florida. "What hasn't been clear," said the study's primary author, Dr. Brenda Sirovich, Staff Physician at the White River Junction VA Medical Center and assistant professor of medicine at DMS, "is whether spending is so different across various areas because the patients are different - in other words, more or less sick - or because the doctors are different. We did this study to find out whether it is in fact differences in doctors, and the decisions they make, that contribute to the large differences in spending that we see."
The study, appearing in the October 24 issue of Archives of Internal Medicine, measured the responses of 5490 primary care physicians to a survey in which they were presented with clinical scenarios and asked how often they would order a specific test, referral, or treatment for each patient described. Sirovich and colleagues used Medicare data to characterize spending in the region where each physician practiced, a figure that ranged from an average of $4911 per capita in the areas of lowest spending to $8325 in the highest spending areas.
The authors found that physicians who practice in areas of high spending do more - they order more tests, referrals, and treatments - than doctors who practice in low spending areas. For example, when presented with a 35-year old man with prolonged back pain and foot weakness after heavy lifting, physicians in high-spending regions would order an MRI scan 82% of the time. This compared to 69% of the time for physicians in low spending regions. For a woman who called complaining of vaginal itching and discharge, physicians in high spending regions would have the patient come in for an office visit 57% of the time compared to 45% for those in low spending regions.
"The strength of this study," Sirovich argues, "is that we were able to isolate the role of physicians in explaining the huge differences that we see in practice and spending across regions."
In previously published work, these researchers have found that providing more medical care was not better in terms of health care quality, satisfaction, or outcomes. In fact, on some measures, such as access to preventive care, high spending regions actually fared worse. Those studies suggest "that care in the U.S. could be just as good or better and cost a lot less - perhaps as much as 30 percent less - if all U.S. regions could safely adopt the more conservative practice patterns of lower-cost regions," said study co-author Dr. Elliott Fisher, professor of medicine at DMS and also a member of the VA Outcomes Group.
The authors acknowledge that it is unlikely that physician behavior is the sole explanation for higher levels of spending in some regions of the country, and that differences in patient expectations may influence spending as well.
In addition to Sirovich and Fisher, Daniel Gottlieb from the Center for the Evaluative Clinical Sciences at DMS and Dr. H. Gilbert Welch, professor of medicine and community and family medicine at DMS and Co-Director of the VA Outcomes Group, are co-authors of the study, which was supported by grants from the Department of Veterans Affairs, the Robert Wood Johnson Foundation, and the National Institute of Aging. The research was conducted at the VA Medical Center in White River Junction, VT, where members of the VA Outcomes Group investigate and promote communication of balanced information about the risks and benefits of medical care.