Search tips
Search criteria 


Logo of hsresearchLink to Publisher's site
Health Serv Res. 1996 June; 31(2): 191–211.
PMCID: PMC1070113

Physician impact on hospital admission and on mortality rates in the Medicare population.


OBJECTIVE. We assess the effect of variations in the supply and specialty distribution of physicians on admission rates for ambulatory care-sensitive conditions (ACS) and for all causes, and on mortality rates among Medicare beneficiaries of various health care service areas (HCSA). DATA SOURCES. For the Medicare beneficiaries, sources were the Health Care Financing Administration's 1992 enrollment and impatient (Part A) files for a 5 percent sample of that population; for the overall populations and for the medical resources of the HCSAs, the Area Resource File. STUDY DESIGN. This observational, cross-sectional study employed multiple linear regression to assess the influence of population characteristics and of the supply of physicians on hospital admissions, and Poisson regression in the analysis of the factors that affect mortality. PRINCIPAL FINDINGS. Physician supply levels vary nearly fourfold or more when comparing the top and bottom deciles of the HCSAs, Medicare admissions for ACS conditions vary about threefold, and admission rates for all causes and mortality rates vary about 1.5-fold. Physician supply levels and distributions have very little influence on ACS admission rates, and even less on the admissions for all causes and on mortality, except in HCSAs with very low physician supply levels (one-fourth the national average or less). However, these HCSAs account for only about 1 percent of the U.S. population. CONCLUSIONS. Physician supply levels and the proportions of specialists and generalists have negligible effects on health status as measured by mortality rates and by rates of admission for all causes and for conditions presumed to be sensitive to the adequacy of ambulatory care. Reductions in admissions for such conditions are not likely to be achieved through broadening of insurance to levels that exist under Medicare, nor through increases in the supply of physicians, nor, conversely, through a reduction in any presumed oversupply of physicians.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.9M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Billings J, Zeitel L, Lukomnik J, Carey TS, Blank AE, Newman L. Impact of socioeconomic status on hospital use in New York City. Health Aff (Millwood) 1993 Spring;12(1):162–173. [PubMed]
  • Caper P. The microanatomy of health care. Health Aff (Millwood) 1993 Spring;12(1):174–177. [PubMed]
  • Chassin MR, Brook RH, Park RE, Keesey J, Fink A, Kosecoff J, Kahn K, Merrick N, Solomon DH. Variations in the use of medical and surgical services by the Medicare population. N Engl J Med. 1986 Jan 30;314(5):285–290. [PubMed]
  • Greenfield S, Nelson EC, Zubkoff M, Manning W, Rogers W, Kravitz RL, Keller A, Tarlov AR, Ware JE., Jr Variations in resource utilization among medical specialties and systems of care. Results from the medical outcomes study. JAMA. 1992 Mar 25;267(12):1624–1630. [PubMed]
  • Krakauer H, Bailey RC. Epidemiologic oversight of the medical care provided to Medicare beneficiaries. Stat Med. 1991 Apr;10(4):521–540. [PubMed]
  • Krakauer H, Bailey RC, Cooper H, Yu WK, Skellan KJ, Kattakkuzhy G. The systematic assessment of variations in medical practices and their outcomes. Public Health Rep. 1995 Jan-Feb;110(1):2–12. [PMC free article] [PubMed]
  • Mullan F. Missing: a national medical manpower policy. Milbank Q. 1992;70(2):381–386. [PubMed]
  • Weissman JS, Epstein AM. The insurance gap: does it make a difference? Annu Rev Public Health. 1993;14:243–270. [PubMed]
  • Wennberg JE, Freeman JL, Shelton RM, Bubolz TA. Hospital use and mortality among Medicare beneficiaries in Boston and New Haven. N Engl J Med. 1989 Oct 26;321(17):1168–1173. [PubMed]

Articles from Health Services Research are provided here courtesy of Health Research & Educational Trust