Related Experiment Video
Updated: May 17, 2026
Digital PCR for Quantifying Circulating MicroRNAs in Acute Myocardial Infarction and Cardiovascular Disease
Published on: July 3, 2018
Comparing the validity of different measures of illness severity: a hospital-level analysis for acute myocardial
Afschin Gandjour1, Meei-Hsiang Ku-Goto, Vivian Ho
1Frankfurt School of Finance & Management, Frankfurt, Germany. a.gandjour@fs.de
Insights
Report cards for acute myocardial infarction (AMI) patients impacted illness severity measures. Charlson and Elixhauser indices proved more valid than prior expenditures for assessing AMI patient severity.
Area of Science:
- Health Services Research
- Medical Informatics
- Cardiovascular Medicine
Background:
- Assessing illness severity is crucial for evaluating hospital performance and patient outcomes.
- Report cards aim to improve healthcare quality by increasing transparency.
- Previous methods for measuring illness severity in acute myocardial infarction (AMI) patients have limitations.
Purpose of the Study:
- To validate three illness severity measures: prior hospital expenditures, Charlson index, and Elixhauser index.
- To analyze the impact of report cards on the illness severity of AMI patients.
- To compare the validity of different severity measures post-report card implementation.
Main Methods:
- Utilized Medicare claims data (1992-1997) for patients aged 65+ with AMI.
- Employed differences-in-differences regression analysis to compare states with and without report cards.
- Validated measures using raw mortality and re-admission trends for AMI patients.
Main Results:
- Prior hospital expenditures suggested a severity change in Pennsylvania, but mortality/re-admission data did not support this.
- Charlson and Elixhauser indices did not indicate significant severity changes in Pennsylvania, aligning with mortality/re-admission trends.
- Illness severity for coronary artery bypass graft (CABG) patients decreased post-report cards, especially in Pennsylvania.
Conclusions:
- Charlson and Elixhauser indices are more valid measures of illness severity for AMI patients than prior hospital expenditures.
- Report cards influenced the selection of CABG patients, favoring healthier individuals and avoiding sicker ones.
- The study highlights the importance of accurate illness severity measurement in healthcare performance evaluation.
Abstract:
The aim of the study is to assess the validity of three measures of illness severity (prior year's hospital expenditures, Charlson and Elixhauser indices), by analysing the effect of introducing report cards on hospitals treating patients with acute myocardial infarction (AMI). Medicare claims data were obtained for 1992-1997 for AMI patients aged 65+. We used differences-in-differences regression analysis to assess the impact of report cards introduced in New Jersey and Pennsylvania on the illness severity of AMI patients with and without coronary artery bypass graft (CABG) surgery (relative to states without report cards). The analysis was conducted at the hospital level. For validation we used raw mortality and re-admission trends for AMI patients. While prior hospital expenditures suggest a considerable change in the illness severity of AMI patients in Pennsylvania relative to other states, raw mortality and re-admission trends in Pennsylvania are relatively consistent with the trend in the rest of the USA. In line with raw mortality and re-admission data, the Charlson and Elixhauser indices do not imply a considerable change in the severity of AMI patients in Pennsylvania. For CABG patients, illness severity - as measured by all three severity measurement methods - decreased after introduction of report cards, particularly in Pennsylvania. In conclusion, for AMI patients the Charlson and Elixhauser indices are a more valid measure of illness severity than prior year's hospital expenditures. After report cards were introduced, healthier AMI patients were more likely to receive CABG surgery, while sicker patients were avoided.
Related Concept Videos
01:30Acute Coronary Syndrome III: Diagnostic Studies
01:19Acute Coronary Syndrome II: Pathophysiology and Clinical Manifestations
01:30Acute Coronary Syndrome I: Introduction
01:20Comparing the Survival Analysis of Two or More Groups
01:27Myocarditis II: Clinical Features and Diagnostic Tests
01:28Acute Coronary Syndrome IV: Interprofessional Care