Published Online
on December 10, 2007

A more recent version of this article appeared on December 18, 2007

This Article Full Text (PDF) Data Supplement Data Supplement All Versions of this Article: 116/25/2960    most recent CIRCULATIONAHA.107.712323v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Stukenborg, G. J. Articles by Connors, A. F. Search for Related Content PubMed PubMed Citation Articles by Stukenborg, G. J. Articles by Connors, A. F., Jr Related Collections Health policy and outcome research

Submitted on April 30, 2007
Accepted on September 21, 2007

Which Hospitals Have Significantly Better or Worse Than Expected Mortality Rates for Acute Myocardial Infarction Patients?. Improved Risk Adjustment With Present-at-Admission Diagnoses

George J. Stukenborg PhD^*, Douglas P. Wagner PhD, Frank E. Harrell Jr PhD, M. Norman Oliver MD, Steven W. Heim MD, Amy L. Price MD, Caroline Kim Han MD, Andrew M.D. Wolf MD, and Alfred F. Connors Jr MD

From the University of Virginia School of Medicine, Charlottesville (G.J.S., D.P.W., M.N.O., S.W.H., C.K.H., A.M.D.W.); Vanderbilt University School of Medicine, Nashville, Tenn (F.E.H.); Eastern Virginia Medical School, Norfolk (A.L.P.); and Case Western Reserve University, Cleveland, Ohio (A.F.C.).

^* To whom correspondence should be addressed. E-mail: gstukenborg{at}virginia.edu.

Background—Public reports that compare hospital mortality rates for patients with acute myocardial infarction are commonly used strategies for improving the quality of care delivered to these patients. Fair comparisons of hospital mortality rates require thorough adjustments for differences among patients in baseline mortality risk. This study examines the effect on hospital mortality rate comparisons of improved risk adjustment methods using diagnoses reported as present-at-admission.

Methods and Results—Logistic regression models and related methods originally used by California to compare hospital mortality rates for patients with acute myocardial infarction are replicated. These results are contrasted with results obtained for the same hospitals by patient-level mortality risk adjustment models using present-at-admission diagnoses, using 3 statistical methods of identifying hospitals with higher or lower than expected mortality: indirect standardization, adjusted odds ratios, and hierarchical models. Models using present-at-admission diagnoses identified substantially fewer hospitals as outliers than did California model A for each of the 3 statistical methods considered.

Conclusions—Large improvements in statistical performance can be achieved with the use of present-at-admission diagnoses to characterize baseline mortality risk. These improvements are important because models with better statistical performance identify different hospitals as having better or worse than expected mortality.

Key words: mortality • myocardial infarction • risk factors • statistics

This article has been cited by other articles:

				C. P. Gale, J. S. Birkhead, and S. O.M. Manda Letter by Gale et al Regarding Article, "Which Hospitals Have Significantly Better or Worse Than Expected Mortality Rates for Acute Myocardial Infarction Patients? Improved Risk Adjustment With Present-at-Admission Diagnoses" Circulation, July 1, 2008; 118(1): e9 - e9. [Full Text] [PDF]

				G. J. Stukenborg, D. P. Wagner, M. N. Oliver, S. W. Heim, C. K. Han, A. M.D. Wolf, F. E. Harrell Jr, A. L. Price, and A. F. Connors Jr Response to Letter Regarding Article, "Which Hospitals Have Significantly Better or Worse Than Expected Mortality Rates for Acute Myocardial Infarction Patients? Improved Risk Adjustment With Present-at-Admission Diagnoses" Circulation, July 1, 2008; 118(1): e10 - e10. [Full Text] [PDF]

				J. V. Tu and P. C. Austin Cardiac Report Cards: How Can They Be Made Better? Circulation, December 18, 2007; 116(25): 2897 - 2899. [Full Text] [PDF]