Hospitalization ambulatory-care sensitive conditions, which are diagnoses treatable in outpatient settings, suggests that the quality of care provided in the outpatient setting was less than ideal. This measure may also represent a tendency to overuse hospitals as a main source of care. Preventable Hospital Stays could be classified as both a quality and access measure, as some literature describes hospitalization rates for ambulatory care-sensitive conditions primarily as a proxy for access to primary health care.
Preventable Hospital Stays is a Rate
Preventable Hospital Stays measures the number of hospital stays for ambulatory-care sensitive conditions per 100,000 Medicare enrollees. Rates measure the number of events (i.e., deaths, births, etc.) in a given time period (generally one or more years) divided by the average number of people at risk during that period. Rates help us compare health data across counties with different population sizes.
The Method for Calculating Preventable Hospital Stays Changed
In the 2019 County Health Rankings, the source for this measure switched from Dartmouth Atlas of Health Care to Mapping Medicare Disparities. The rate also switched from per 1,000 to 100,000 Medicare enrollees. The definition of hospitalizations also changed. Previously, hospitalizations for the following conditions were included: Convulsions, Chronic Obstructive Pulmonary Disease, Bacterial Pneumonia, Asthma, Congestive Heart Failure, Hypertension, Angina, Cellulitis, Diabetes, Gastroenteritis, Kidney/Urinary Infection, and Dehydration. See the numerator definition below for current hospitalizations included.
A limitation of this measure is that it uses Medicare claims data, which limits the population evaluated to mostly individuals age 65 and older. This measure, therefore, may potentially miss trends and disparities among younger age groups.
The numerator is the number of discharges for Medicare beneficiaries ages 18 years or older continuously enrolled in Medicare fee-for-service Part A and hospitalized for any of the following reasons: diabetes with short or long-term complications, uncontrolled diabetes without complications, diabetes with lower-extremity amputation, chronic obstructive pulmonary disease, asthma, hypertension, heart failure, dehydration, bacterial pneumonia, or urinary tract infection.
The denominator is the Medicare beneficiaries ages 18 years or older continuously enrolled in Medicare fee-for-service Part A.
Years of Data Used
Mapping Medicare Disparities Tool
The Centers for Medicare & Medicaid Services Office of Minority Health's Mapping Medicare Disparities (MMD) Tool contains health outcome measures for all states and counties for disease prevalence, costs, hospitalization for 55 specific chronic conditions, emergency department utilization, readmissions rates, mortality, preventable hospitalizations, and preventive services.
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