IDENTIFYING PROCESS VARIATION VIA RISK-ADJUSTED OUTCOME (CORONARY ARTERY BYPASS GRAFT, MORTALITY).
Contributors: University of California, San Francisco.
Published: 1995
Number of pages: 349
Subjects: Health Sciences, Nursing.; Health Sciences, Health Care Management.; Health Sciences, Medicine and Surgery.
Description: The purpose of this investigation was to examine the efficacy of using discharge abstract-based risk-adjustment of Department of Defense (DOD) coronary artery bypass graft surgery (CABGS) mortality to examine process differences between DOD medical centers. Inputs and processes of CABGS surgery were described and process differences between DOD medical centers with higher and lower risk-adjusted CABGS mortality rates were analyzed using a combination of case and control and descriptive research designs.

The research had two phases. Phase I consisted of secondary analysis of all DOD CABGS discharge abstract data in order to examine patient severity of illness (SOI). Phase IIA involved observation of the hemodynamic processes of CABGS personnel at each of 6 DOD medical centers: 2 case (higher mortality) and 4 control (lower and median mortality). Phase IIB involved written survey of DOD CABGS care personnel concerning hemodynamic knowledge and organizational processes. Phase IIC involved collection of CABGS SOI and care process data at case and control medical centers via retrospective chart audit.

The risk-adjusted model of CABGS mortality developed via logistic regression from the discharge abstract data included the variables of acute myocardial infarction, age, repeat CABGS, female sex, diabetes mellitus, and hypertension. The model was significant (p =.000) and demonstrated good calibration and discrimination. All DOD medical centers had actual mortality that was less than that predicted by the risk-adjustment: crude and risk-adjusted mortality rates were highly correlated (Spearman's rho =.93).

Significant (t-test) differences in CABGS care inputs and processes were noted between DOD medical centers with higher and lower risk-adjusted mortality including: provider pulmonary artery catheter knowledge (p =.004); cardiopulmonary bypass time (p =.000); aortic cross-clamp time (p =.000); and post-CABGS (p =.001) and hospital (p =.000) lengths of stay. Reliability and validity problems of DOD discharge abstract data were identified.

DOD discharge abstract-based risk-adjustment is possible and could be useful in quality improvement screening to identify outcome, input, and process outliers. Collection of clinical process data in conjunction with SOI risk-adjustment would give providers information for benchmarking their care and direction toward areas requiring improvement.
Notes: Source: Dissertation Abstracts International, Volume: 56-11, Section: B, page: 6032.

Thesis (PH.D.)--UNIVERSITY OF CALIFORNIA, SAN FRANCISCO, 1995.

School code: 0034.