Risk and Outcome Assessments
The assessment of outcomes in medicine at an institutional and practitioner level has become target of intense scrutiny in the current practice of organized medicine. Comparison of outcomes among providers and against established benchmarks has become commonplace for the purpose of hospital accreditation and as an essential tool in the selection of providers by the consumer. Therefore, the establishment of valid metrics in the assessment of outcomes and the accurate risk-adjusted comparison of them is critical in the modern practice of medicine.
The reporting of outcomes in cardiac surgery has evolved from the release of raw mortality rates to the risk-adjusted assessment of various endpoints following an index intervention. With the advent of less invasive interventions as options for the treatment of coronary and valve pathology, there has been a significant increase in the risk profile of patients undergoing cardiac surgery and thus a wide variability in the risk profile of patients presenting to various institutions. Consequently, the establishment of accurate risk models with periodic calibration is essential to adjust for an ever-changing patient risk profile.
With the heightened scrutiny on quality measures among institutions and practitioners, it is imperative to establish effective methods of risk assessment and outcome comparison. The reporting of outcomes, initially limited to raw mortality rates, has evolved over the last three decades into the calculation of risk-adjusted metrics of a variety of quality indicators. With the intricate evolution in the complexity of organized medicine, practitioners face increasing oversight by private- and government-based regulatory entities; therefore, it is incumbent to the medical community to be knowledgeable on the various strategies in the assessment of the quality of care provided.
The current chapter intends to describe the essentials in the process of risk adjustment and to present some of the most commonly utilized registries pertinent to the practice of cardiac surgery.
KeywordsRisk Outcome Risk modeling Goodness of fit Model validation Risk-adjusted comparison metrics Observed-to-Expected ratio Propensity score analysis The Medicare Provider Analysis and Review (MedPAR) California Discharge Database National inpatient sample (NIS) New York State Department of Health (NYS DOH) Veterans Administration Database Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (ACSD) New York Heart Association (NYHA) STS cardiac surgery risk calculator EuroSCORE
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