A NOTE ON METHODOLOGY: HOW WE CALCULATED THE BEST HOSPITALS FOR AMERICA.

• Author: Saini, Vikas

The Lown Institute Hospitals Index rankings are based on three categories of data: quality of care, civic leadership, and value of care. These were weighted at 50,30, and 20 percent respectively in the final rankings. The three categories comprise seven sub-components, each of which includes more detailed measurements. The detailed measurements were rolled up into their respective components and categories to obtain a final score for each hospital.

We defined our set of hospitals based on the ability to calculate mortality rates using the Medicare Provider Analysis and Review administrative claims data set. Hospitals with fewer than 50 admissions per year were excluded. Hospitals specializing in cancer care and orthopedic or cardiac procedures were also excluded. Information on hospital characteristics was obtained from the American Hospital Association annual survey and from Medicare. We excluded hospitals that were not acute care or were located outside the 50 states and Washington, D.C. We also excluded federal hospitals, such as hospitals in the Veterans Health Administration, and hospitals where a majority of patients are covered by Medicare Advantage (Kaiser Permanente, for example). This left 3,362 hospitals, 545 of which are for-profit, 2,188 nonprofit, and 629 public.

Quality of Care

The quality of care category is made up of three components: clinical outcomes, patient safety, and patient satisfaction, which were weighted in a ratio of 5:2:1 respectively. This weighting ensured that clinical outcomes had the greatest impact on the final quality score. Clinical outcomes is composed of risk-standardized rates of mortality and readmission, weighted 4:1. Mortality includes rates of in-hospital, 30day, 90-day, and one-year mortality. These were weighted in a ratio of 4:4:2:1 respectively in an effort to balance the effects of hospital-based care with post-discharge care and coordination in the community. For the readmission component, we equally weighted 30-day readmission rates, a standard measure of quality, and seven-day readmission, as published data suggests that the hospital-attributable component of readmission rates wanes by the seven-day mark.

Hospitalization and readmission rates were calculated after adjusting for patient risks using the Risk Stratification Index (RSI), a Lown Institute-specific version of a machine-learning algorithm in the public domain that has been validated on multiple national, state-based, and...