Ratings of providers and physicians have become an increasingly important feature of healthcare consumer information. The 5-Star Quality Rating System represents an initial attempt by CMS to consolidate a diverse set of seven metrics about dialysis facility performance into a single consumer-friendly score, expressed as anywhere from one to five stars. The design and methodology of this first foray into rating facilities, however, is clearly complicated by limitations.
Each of the seven constituent metrics by itself presents challenges. The standardized outcome ratios — for mortality, hospitalization, and transfusion — each depend on risk adjustment, which includes consideration of comorbidity as ascertained from the Medical Evidence (ME) Report. Data presented in the chapter on incidence suggest that the ME Report does not accurately capture comorbidity at incidence, at least in elderly patients. Even if the ME Report were a perfectly valid instrument, the question remains whether the recorded conditions are sufficient and timely descriptors of patient health, especially in unique subgroups, such as patients with little recorded health history at dialysis initiation or those transferring from one facility to another. In the domain of vascular access measures there is no risk adjustment. This may be problematic in terms of older and diabetic patients, in whom the preservation of arteriovenous fistulas may be difficult (due to the health of the peripheral vasculature) or not necessarily efficacious, as literature has begun to suggest may be true for very elderly patients. In the domain of other measures regarding dialysis adequacy and hypercalcemia, it is simply uncertain to what the degree the limited amount of variation among dialysis facilities correlates with meaningful differences in the quality of dialysis patient care and corresponding patient outcomes.
Challenges with the metrics are already known. In the case of star ratings, the difficulty with the whole may be more profound than the sum of the difficulties of the parts. The 5-Star Quality Rating System combines process measures and standardized outcome ratios with a mathematical function that places an implicit relative valuation on each of the seven metrics. The conceptual difficulty is that each consumer may value metrics or domains in different ways than CMS values them. From this perspective, the convenience of a single rating for each dialysis facility is limited by the imposition of a value system that parties other than the payer may not hold. This is not a patient-centered system, despite its best intentions.
The Peer Kidney Care Initiative is devoted to improving the quality of dialysis patient care. The data throughout this inaugural Peer Report indicate that dialysis patient outcomes are varied. The clinical challenges that present in the first year of treatment are not the same as those presenting later. There are profound geographic differences in patient outcomes, so much so that it is difficult to refute the hypothesis that overarching health of local populations, conditions of the natural and economic environments, and capacity and capability of the healthcare delivery systems do not exert their influence on dialysis patient outcomes quite apart from the narrow scope of outpatient dialysis providers. There is profound of seasonality of outcomes, with respect not only to infectious complications, but also to cardiovascular complications, respiratory complications, mortality, and even the very incidence of end-stage renal disease. The 5-Star Quality Rating System does not consider these issues in a rigorous manner, and thereby misses an opportunity to inspire meaningful improvements in the quality of dialysis patient care.
In the future, the Peer Kidney Care Initiative will further organize these and other data — including information about the incidence of acute care in the emergency department, the incidence and treatment of infection in all settings, and the health of the growing population of patients dialyzing at home — in a more rigorous framework, one that describes the quality of patient care in ways that consolidate information without imposing relative valuations on specific domains, so that all stakeholders in the community, including patients, physicians, providers, payers, and state and federal governments, may continue to realize improvements in care and outcomes.