Challenges in Risk Adjustment for Hospital and Provider Outcomes Assessment

How are we to evaluate outcomes for the care that we provide, and how are we to benchmark ourselves compared with colleagues at other institutions? It is critical that we do this to improve our own performance, and it is also being demanded of us by other stakeholders in society. Indeed, regular public reporting of outcomes is now effectively mandated of providers in many medical disciplines, and standards for statistical adjustment have been developed.1 As a result, performance reports based on data from both administrative and clinical databases are commonplace, with a few elite databases serving as de facto sources of truth for medical performance in the United States. However, important questions must be asked about the registries being used to set performance standards and inform medical regulatory policies. Within cardiology, one of the most commonly reported metrics is mortality after revascularization, either in-hospital or some time thereafter, often 30 days. Such reporting may be at the level of the individual operator, hospital, or health care system. Other metrics, including nonfatal events and cost, are also reported commonly.2 Initial public reports several decades ago offering raw outcome statistics on these end points resulted in a firestorm of criticism that the published data did not appropriately account for patient differences. In recent years, efforts have been made to account for variation in severity of illness, acuteness of presentation, and comorbidities using statistical methods that risk adjust to create fairer comparisons.1 Concerns now focus on metrics such as risk-adjusted …