Computerized Adjudication of Coronary Heart Disease Events Using the Electronic Medical Record in HIV Clinical Research: Possibilities and Challenges Ahead.

This pilot study assessed feasibility of computer-assisted electronic medical record (EMR) abstraction to ascertain coronary heart disease (CHD) event hospitalizations. We included a sample of 87 hospitalization records from participants the University of North Carolina (UNC) site of the Women's Interagency HIV Study (WIHS) and UNC Center for AIDS Research (CFAR) HIV Clinical Cohort who were hospitalized within UNC Healthcare System from July 2004 to July 2015. We compared a computer algorithm utilizing diagnosis/procedure codes, medications, and cardiac enzyme levels to adjudicate CHD events [myocardial infarction (MI)/coronary revascularization] from the EMR to standardized manual chart adjudication. Of 87 hospitalizations, 42 were classified as definite, 25 probable, and 20 non-CHD events by manual chart adjudication. A computer algorithm requiring presence of ≥1 CHD-related International Classification of Diseases, 9th Revision (ICD-9)/Current Procedural Terminology (CPT) code correctly identified 24 of 42 definite (57%), 29 of 67 probable/definite CHD (43%), and 95% of non-CHD events; additionally requiring clinically defined cardiac enzyme levels or administration of MI-related medications correctly identified 55%, 42%, and 95% of such events, respectively. Requiring any one of the ICD-9/CPT or cardiac enzyme criteria correctly identified 98% of definite, 97% of probable/definite CHD, and 85% of non-CHD events. Challenges included difficulty matching hospitalization dates, incomplete diagnosis code data, and multiple field names/locations of laboratory/medication data. Computer algorithms comprising only ICD-9/CPT codes failed to identify a sizable proportion of CHD events. Using a less restrictive algorithm yielded fewer missed events but increased the false-positive rate. Despite potential benefits of EMR-based research, there remain several challenges to fully computerized adjudication of CHD events.