Background: The Australian healthcare system is complex. Assessing the quality of the care provided in the management of acute coronary syndromes (ACS) is problematic because of disparate systems that constrain an integrated reporting approach. Registry data reported within a comparative effectiveness research (CER) framework establishes the case for clinical process indicators to measure and report hospital performance. Objectives: To aggregate data from The Global Registry of Acute Coronary Events (GRACE) and the Cooperative National Registry of Acute Coronary Care Guideline Adherence and Clinical Events (CONCORDANCE) to describe temporal trends in the management of ACS and associations with in-hospital events, hospital readmission and six month mortality; to develop a composite score of hospital performance quality; to determine associations between adherence to the quality composite score and in-hospital events, hospital readmission and six month mortality and develop a benchmarked stakeholder hospital performance report. Methods: A single case study embedding three units of analysis was used to explore and explain how data reported in a CER framework measures hospital performance in the management of ACS. Analysis: Descriptive analyses of prospectively collected data on the management and outcomes of over 7000 patients admitted to 46 hospitals from 1999 to 2016. Findings: The first Unit of Analysis reports temporal trends in the management of ACS across 11 hospitals in the GRACE registry from 2000 to 2007 which informed the design of the CONCORDANCE registry; The second Unit of Analysis combines both GRACE and CONCORDANCE registries and reports on the management of ST-elevation acute myocardial infarction (STEMI ) from 1999 to 2016 revealing gains in pre-hospital care and fewer in-hospital clinical events, and readmission for urgent revascularisation without a significant reduction in in-hospital or six month mortality. The third Unit of Analysis reports the observed and risk-adjusted association between adherence to the quality composite score and reduced in-hospital events, and increased survival at hospital discharge and at six months post discharge. Conclusion: Case-study analysis of CER in the context of ACS registries provides evidence on adherence to evidence-based care and a quality composite measure of hospital performance in the management of ACS
