Special Report

Cities Where You Don't Want to Get Sick

To determine the cities with the worst hospitals, 24/7 Wall St. created an index using data from the Centers for Medicare and Medicaid Services (CMS) and other sources. The CMS produces statistics on numerous health measures for most hospitals in the country. We grouped hospitals by their respective metropolitan areas and aggregated each measure to the city level.
Each datapoint was converted into an index using the min-max normalization method. The composite index was calculated from each individual index. A hospital’s mortality rate was given 40% weight. The Leapfrog Group’s safety score made up 30% of the index, readmission rates comprised 20%, and the rate of preventable hospitalizations was given a 15% weight.

First, we calculated a weighted average of 30-day mortality rates for heart attacks, chronic obstructive pulmonary disease (COPD), coronary artery bypass grafting (CABG), heart failure, pneumonia, and stroke to find the average percentage of people who died within 30 days of being admitted to a hospital. For many experts, 30 days is an appropriate window in which a hospital, rather than individual behavior, is at fault for a patient’s death. All mortality rates are risk adjusted.

Second, we included the rate at which individuals were readmitted to a hospital within 30 days of being discharged. Like mortality rates, readmission within 30 days speaks to a health system’s low quality of care and poor communication between hospitals and ambulatory care facilities rather than individual behavior.

We also included the Leapfrog Group’s hospital grading, which considers a host of objective measures related to a hospital’s care delivery as well as responses of patient surveys. Grades range from A to F. To quantify each measure, we assigned A grades a score of 90, B grades a score of 80, and so on. We only included hospitals that existed in both the CMS data and the Leapfrog Group’s data.

Lastly, we used the share of hospitalizations for conditions that could have been treated at outpatient or ambulatory care facilities — often referred to as the unnecessary hospitalization rate. Included in this measure is hospitalization for conditions such as asthma, dehydration, or hypertension. This data came from County Health Rankings.