title: Small primary care physician practices have low rates of preventable hospital admissions.
abstract: Nearly two-thirds of US office-based physicians work in practices of fewer than seven physicians. It is often assumed that larger practices provide better care, although there is little evidence for or against this assumption. What is the relationship between practice size--and other practice characteristics, such as ownership or use of medical home processes--and the quality of care? We conducted a national survey of 1,045 primary care-based practices with nineteen or fewer physicians to determine practice characteristics. We used Medicare data to calculate practices' rate of potentially preventable hospital admissions (ambulatory care-sensitive admissions). Compared to practices with 10-19 physicians, practices with 1-2 physicians had 33 percent fewer preventable admissions, and practices with 3-9 physicians had 27 percent fewer. Physician-owned practices had fewer preventable admissions than hospital-owned practices. In an era when health care reform appears to be driving physicians into larger organizations, it is important to measure the comparative performance of practices of all sizes, to learn more about how small practices provide patient care, and to learn more about the types of organizational structures--such as independent practice associations--that may make it possible for small practices to share resources that are useful for improving the quality of care.
authors.affiliation: Lawrence P. Casalino (lac2021@med.cornell.edu) is the Livingston Farrand Professor in the Department of Healthcare Policy and Research at Weill Cornell Medical College, in New York, New York.
authors.forename: Lawrence P
authors.initials: LP
authors.lastname: Casalino
authors.affiliation: Michael F. Pesko is an assistant professor in the Department of Healthcare Policy and Research, Weill Cornell Medical College.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Pesko
authors.affiliation: Andrew M. Ryan is an associate professor in the Department of Healthcare Policy and Research, Weill Cornell Medical College.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Ryan
authors.affiliation: Jayme L. Mendelsohn worked on this project as a research coordinator in the Department of Healthcare Policy and Research, Weill Cornell Medical College. She is currently a postbaccalaureate premedical student at Bryn Mawr.
authors.forename: Jayme L
authors.initials: JL
authors.lastname: Mendelsohn
authors.affiliation: Kennon R. Copeland is senior vice president and director in the Department of Statistics and Methodology, NORC at the University of Chicago, in Illinois.
authors.forename: Kennon R
authors.initials: KR
authors.lastname: Copeland
authors.affiliation: Patricia Pamela Ramsay is a research specialist at the School of Public Health, University of California, Berkeley.
authors.forename: Patricia Pamela
authors.initials: PP
authors.lastname: Ramsay
authors.affiliation: Xuming Sun worked on this project as a research biostatistician in the Department of Healthcare Policy and Research, Weill Cornell Medical College. She is currently working as a statistician in the New York City Department of Health and Mental Hygiene.
authors.forename: Xuming
authors.initials: X
authors.lastname: Sun
authors.affiliation: Diane R. Rittenhouse is an associate professor in the Department of Family and Community Medicine and Center for Excellence in Primary Care, University of California, San Francisco.
authors.forename: Diane R
authors.initials: DR
authors.lastname: Rittenhouse
authors.affiliation: Stephen M. Shortell is the Blue Cross of California Distinguished Professor of Health Policy and Management at the School of Public Health, University of California, Berkeley.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Shortell
mesh_terms: D000368:Aged; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D006278:Medicare; D010824:Physicians' Offices; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011320:Primary Health Care; D058996:Quality Improvement; D011787:Quality of Health Care; D011795:Surveys and Questionnaires; D014481:United States
keywords: Cost of Health Care; Organization and Delivery of Care; Primary Care; Quality Of Care