Impact of Risk Adjusted Clinical Outcomes Methodology-Quality Measures on Hospital Mortality Data: A Statistical and Case Study Approach

Abstract

The effectiveness of risk adjustment in improving mortality as a performance measure for hospitals remains uncertain. New techniques of risk adjustment should be empirically tested, and health care professionals, using the data derived from such measures, should be queried before final acceptance of these technologies of measurement is warranted. The Risk Adjusted Clinical Outcomes Methodology-Quality Measures (RACOM-QM), a relatively new risk-adjustment methodology developed by the QuadraMed Corporation, was used by Maryland hospitals for risk adjustment for the first time in 1997. A research study was undertaken by the Maryland Hospital Association to determine the impact of RACOM-QM on mortality rates, its empirical validity, and its acceptance in the field. The relationship between RACOM-QM mean risk scores and mortality rates was examined using inpatient hospital mortality data for Maryland in 1996. Using these same data, the empirical relationship between risk-adjusted and unadjusted mortality by diagnosis-related group (DRG) was also investigated. Case studies were undertaken to glean information about the use and acceptability of this new methodology in 2 hospital settings in Maryland. There was a strong relationship between mean mortality risk scores and mortality rates. The analysis of the empirical relationship between risk-adjusted and unadjusted mortality by DRG yielded support for the impact of RA-COM-QM in adjusting inpatient mortality rates. The case studies supported the utility of this method of risk adjustment in increasing the interpretation of mortality data and in helping to identify areas in which to investigate quality in more depth in 2 hospital settings. This study provides overall support for the usefulness of risk adjustment and, specifically, the RACOM-QM, in increasing the interpretation of inpatient mortality rates in Maryland's acute care hospitals. This study also suggests that use of the RACOM-QM improved comparative analysis of inpatient mortality rates among Maryland hospitals. Finally, the results of the case study analysis suggest that improved internal review of mortality rates and increased clinician acceptance of these rates as indicators of performance were enhanced by the use of a risk adjustment methodology.

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