Hospital Quality Guide Methodology 2006 5
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May not be reprinted or reproduced without permission from Health Grades, Inc.
Medical Issues Rating Methodologies
HealthGrades rates hospitals using a number of methodologies:
Risk adjustment methodologies (HealthGrades proprietary and APR-DRGs)
Programmatic evaluations (Maternity Care and Women's Health)
How HealthGrades Rates Hospitals: Except Maternity Care and Women's Health
For each hospital, HealthGrades rated different procedures or diagnoses using risk adjustment
methodologies (except Maternity Care and Women's Health). Each of the procedures or diagnoses is rated
in one or more categories:
Survival and Recovery ratings are based upon mortality outcomes while Avoiding Complications is based
upon complication outcomes.
HealthGrades risk adjusts the data to ensure a fair comparison between hospitals. Each hospital receives
one of the following ratings for each medical issue:
Ratings are based upon two different risk adjustment methodologies:
HealthGrades' proprietary risk adjustment methodology
All Patient Refined Diagnosis Related Groups (APR-DRGs)
HealthGrades' Proprietary Risk Adjustment Methodology
For 27 medical issues, the risk adjustment is based upon a proprietary HealthGrades methodology.
Developing ratings involved two steps. First, the predicted value for a specific outcome is estimated.
Second, the predicted outcome was compared to the actual outcome.
HealthGrades further determines if the difference between the predicted outcome and the actual outcome is
statistically significant. This is important because in health care, patients differ from one another with respect
to their health status, demographics, and type of procedure performed. Risk factors include sex, age,
specific procedure performed, and current health conditions such as hypertension, diabetes, and congestive
heart failure. The risk adjustment methodology HealthGrades uses takes these factors into consideration to
make fair and accurate comparisons of hospitals based upon the types of patients treated.