Researchers have devised a new Risk Stratification Index (RSI) that allows clinical outcomes such as length-of-stay and mortality for surgical patients to be accurately compared among hospitals using only publicly available billing data. The new index system, published in the journal Anesthesiology, is considered more accurate than existing outcomes measurements such as the Charlson Comorbidity Index (CCI).

“Standardized risk stratification metrics coupled with outcome and cost measures are central to the success of the existing healthcare model,” said Daniel I. Sessler, MD, professor and chair of the department of outcomes research at the Cleveland Clinic. “Clinicians and hospitals use major outcomes to evaluate performance and guide improvement efforts. Patients and insurers also use outcomes to select hospitals. However, outcomes from various hospitals can only reasonably be compared after adjusting for patients’ baseline risk and the risk associated with different operations. Our Risk Stratification Index permits outcomes such as duration of hospitalization and mortality to be compared fairly across institutions.”

To develop the RSI, Sessler and his team analyzed more than 35 million Medicare records dating from 2001 to 2006. From these records, the researchers developed highly predictive risk-adjustment models for length-of-stay, and for in-hospital, 30-day, and 1-year mortality. The validity of the system was then confirmed by applying the system to the Cleveland Clinic.

“An important aspect of our Risk Stratification models is they are entirely objective, reproducible, and transparent; they do not include any ‘adjustments’ or subjective ‘fixes.’ The system thus provides a transparent and fair basis for comparing outcomes among hospitals,” said Sessler.

While the new RSI is considered a welcome contribution to the quality and uniformity of hospital outcome reporting, two reviewers note some potential shortcomings of the system, particularly the use of Medicare claims (billing) database.

“Applying RSI methodology to current physician payment administrative claims data will be unlikely to generate as robust a formula for predicting mortality, morbidity, or other endpoints as the authors demonstrated here with inpatient data. However, reorganization of Medicare contracting into combined Part A and B Medicare Administrative Contractors has the potential to link patient-specific quality, cost, facility, and provider data in a way that could allow a modified RSI to include quality and cost inputs,” wrote Alexander A. Hannenberg, MD, and Norman A. Cohen, MD, in a recent review.

In a second review of the RSI, Fredrick K. Orkin, MD, concurred with Hannenberg and Cohen. He also wrote, “While Sessler et al. propose using their methodology for public reporting of hospital-level outcomes, the notion of report cards is problematic: Consumers pay more attention to ratings when buying a toaster than selecting hospitals, possibly due to restriction imposed by their health insurance plans.”

Sessler and his research team have committed to releasing their RSI into the public domain, including future updates and potential extensions to out clinical endpoints and other types of administrative data.

Source: American Society of Anesthesiologists