Hospital Report Cards TM Maternity Care and Women's Health Methodology 2007-2008 5
© Copyright 2007 Health Grades, Inc. All rights reserved.
May not be reprinted or reproduced without permission from Health Grades, Inc.
Methodology for Women's Health
The Women's Health ratings were based upon outcomes in two areas: maternity care (methodology
described above) and cardiac/stroke mortality outcomes for women. Hospitals had to have an overall rating
from each area to be considered.
Methodology for Cardiac and Stroke Mortality Ratings for Women
HealthGrades analyzed the following six procedures/diagnoses (cohorts) for each hospital's female patients:
·
Coronary bypass surgery
·
Valve replacement surgery
·
Interventional cardiology procedures (PTCA/angioplasty, stent, atherectomy)
·
Heart attack
·
Heart failure
·
Stroke
Data Analysis
For each patient cohort, HealthGrades developed a list of specific procedures to be included in the cohort
(e.g., quadruple bypass surgery), and a list of potential risk factors. The list of risk factors was developed in
two steps:
1. HealthGrades identified all diagnoses occurring in more than 0.5 percent of the patients.
2. Some diagnosis codes were merged together (e.g., primary and secondary pulmonary hypertension) to
minimize the impact of coding differences. Outcomes were binary, with patients recorded as either alive
or expired. A list of the codes used to identify patients in the six cohorts can be found in Exhibit A.
Risk-Adjustment Methodology
The purpose of risk adjustment is to obtain fair statistical comparisons between disparate populations or
groups. Significant differences in demographic and clinical risk factors are found among patients treated in
different hospitals. Risk adjustment of the data is needed to make accurate and valid comparisons of clinical
outcomes at different hospitals.
Fair and valid comparisons between hospital providers can be made only to the extent that the risk-
adjustment methodology considers important differences in patient demographic and clinical characteristics.
The risk-adjustment methodology used by HealthGrades defines risk factors as those clinical and
demographic variables that influence patient outcomes in significant and systematic ways. Risk factors may
include age, specific procedure performed, and comorbid conditions such as hypertension, chronic renal
failure, congestive heart failure, and diabetes.
