Scope of Care Coordination Daunting for Physicians Treating Medicare Patients

    • February 16, 2009

Illustrating the formidable task of coordinating care, a typical primary care physician who treats elderly Medicare patients must coordinate care with 229 other physicians working in 117 different practices, according to a study by researchers at the Center for Studying Health System Change (HSC), Memorial Sloan-Kettering Cancer Center (MSKCC) and the Dana-Farber Cancer Institute in the February 17 Annals of Internal Medicine.

“The logistical challenges to care coordination are daunting given the fragmentation of care and the large number of peers that physicians must interact with when treating Medicare patients,” said Hoangmai H. Pham, M.D., M.P.H., the study’s lead author and an HSC senior health researcher.

Policy-makers and insurers are searching for strategies to improve care coordination and reinvigorate primary care as a critical component of reforming the U.S. health care system. As Medicare and private health plans experiment with extra payments to primary care physicians to coordinate care—for example, through medical homes—the study findings suggest that substantial delivery system reforms may be needed to make such models work.

“Without changes that foster increased integration of physicians—either in virtual or actual organizations—care coordination is likely to remain an ideal but elusive goal in Medicare,’ Pham said.

The study, “Primary Care Physicians’ Links to Other Physicians Through Medicare Patients:  The Scope of Care Coordination,” is based on HSC’s nationally representative 2004-05 Community Tracking Study Physician Survey, which collected information from 6,600 practicing physicians, and Medicare claims information on beneficiaries these physicians treated in 2005. Data on physicians and patients were linked with the use of the physicians’ unique provider identification number, and a total of 2,284 primary care physicians and 576,875 elderly Medicare patients were included in the study.

Each primary care physician in the study treated an average of 264 unique Medicare fee-for-service patients. For every 100 Medicare patients treated, each primary care physician would typically have to communicate with 99 physicians in 53 practices to coordinate care, the study found. Physicians who treated patients with more chronic conditions (patients in the highest quartile of chronic illness burden) typically had to interact with 134 physicians in 62 practices for every 100 Medicare patients.

The study also found that physicians working in solo or two-person practices had more peers (median, 69 practices per 100 Medicare patients) than physicians in larger group practices and institutional work settings. The median number of practices among peers per 100 Medicare patients was higher in urban areas (median, 60 practices) than in rural areas (median, 36 practices).

The number of physician peers also varied across Census regions, ranging from a median of 37 practices per 100 Medicare patients in the East South Central Region (Alabama, Kentucky Mississippi and Tennessee) to 81 practices in the Mid-Atlantic region (New Jersey, Ney York and Pennsylvania). Likewise, the number of physician peers steadily increased with the supply of specialist physicians in the metropolitan area where the primary care physician practiced. For example, primary care physicians in the highest quintile of specialist physicians per 1,000 capita had to coordinate care with 143 physicians in 62 practices per 100 Medicare patients.

The study was coauthored by HSC Senior Researcher Ann O’Malley, M.D., M.P.H.; Peter B. Bach, M.D., M.A.P.P., of the Department of Epidemiology and Biostatistics at MSKCC; Cynthia Saiontz-Martiniz, Sc.M., of Social Scientific Systems; and Deborah Schrag, M.D., M.P.H., of the Dana-Farber Cancer Institute; and was funded by the National Institute on Aging, the Robert Wood Johnson Foundation and the American Medical Group Association.


The Center for Studying Health System Change is a nonpartisan policy research organization committed to providing objective and timely research on the nation’s changing health system to help inform policy makers and contribute to better health care policy. HSC, based in Washington, D.C., is funded in part by the Robert Wood Johnson Foundation and affiliated with Mathematica Policy Research, Inc.