Validation of HIV ‐infected cohort identification using automated clinical data in the Department of Veterans Affairs

Objectives The US Department of Veterans Affairs ( VA ) is the largest integrated health care provider for HIV ‐infected patients in the US A. VA data for HIV ‐specific clinical and quality improvement research are an important resource. We sought to determine the accuracy of using the VA Corporate Data Warehouse ( CDW ), a fully automated medical records database for all VA users nationally, to identify HIV ‐infected patients compared with a gold‐standard VA HIV Clinical Case Registry ( CCR ). Methods We assessed the test performance characteristics of each of our CDW criteria‐based algorithms (presence of one, two or all of the following: diagnostic codes for HIV , positive HIV laboratory tests, and prescription for HIV medication) by calculating their sensitivity (proportion of HIV ‐positive patients in the CCR accurately detected as HIV ‐positive by the CDW algorithm) and positive predictive value ( PPV ; the proportion of patients identified by the CDW algorithm who were classified as HIV ‐positive from the CCR ). Results We found that using a CDW algorithm requiring two of three HIV diagnostic criteria yielded the highest sensitivity (95.2%) with very little trade‐off in PPV (93.5%). Conclusions A two diagnostic criteria‐based algorithm can be utilized to accurately identify HIV ‐infected cohorts seen in the nationwide VA health care system.