Resource utilization in treatment of acute myocardial infarction: staff-model health maintenance organization versus fee-for-service hospitals. The MITI Investigators. Myocardial Infarction Triage and Intervention

J Am Coll Cardiol. 1995 Aug;26(2):401-6. doi: 10.1016/0735-1097(95)80013-7.


Objectives: This study sought to compare the use of invasive procedures and length of stay for patients admitted with acute myocardial infarction to health maintenance organization (HMO) and fee-for-service hospitals.

Background: The HMOs have reduced costs compared with fee-for-service systems by reducing discretionary admissions and decreasing hospital length of stay. It has not been established whether staff-model HMO hospitals also reduce the rate of procedure utilization.

Methods: Using data from a retrospective cohort, we performed univariate and multivariate comparisons of the use of cardiac procedures, length of stay and hospital mortality in 998 patients admitted to two staff-model HMO hospitals and 7,036 patients admitted to 13 fee-for-service hospitals between January 1988 and December 1992.

Results: The odds of undergoing coronary angiography were 1.5 times as great for patients admitted to fee-for-service hospitals than for those admitted to HMO hospitals (odds ratio 1.5, 95% confidence interval [CI] 1.3 to 1.9). Similarly, the odds of undergoing coronary revascularization were two times greater in fee-for-service hospitals (odds ratio 2.0, 95% CI 1.6 to 2.5). However, higher utilization was strongly associated with the greater availability of on-site cardiac catheterization facilities in fee-for-service hospitals. The length of hospital stay, by contrast, was approximately 1 day shorter in the fee-for-service cohort (7.3 vs. 8.0 days, p < 0.05).

Conclusions: Physicians in staff-model HMO hospitals use fewer invasive procedures and longer lengths of stay to treat patients with acute myocardial infarction than physicians in fee-for-service hospitals. This finding, however, appears to be associated with the lack of on-site catheterization facilities at HMO hospitals.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Analysis of Variance
  • Confounding Factors, Epidemiologic
  • Coronary Angiography / economics
  • Coronary Angiography / statistics & numerical data*
  • Fee-for-Service Plans / economics*
  • Fee-for-Service Plans / statistics & numerical data
  • Female
  • Health Maintenance Organizations / economics*
  • Health Maintenance Organizations / statistics & numerical data
  • Hospital Administration / economics*
  • Hospital Mortality
  • Humans
  • Length of Stay / statistics & numerical data
  • Male
  • Middle Aged
  • Myocardial Infarction / diagnosis*
  • Myocardial Infarction / mortality
  • Myocardial Infarction / therapy*
  • Myocardial Revascularization / economics
  • Myocardial Revascularization / statistics & numerical data*
  • Odds Ratio
  • Retrospective Studies
  • Triage
  • United States
  • Washington