Background:  The CDC recommends routine (nontargeted) opt-out HIV screening in healthcare settings, including emergency departments (ED). Since 2006, 11 studies have reported only modest effectiveness of nontargeted screening in this clinical setting. Recently, a risk prediction tool, the Denver HIV Risk Score (DHRS), was developed to more specifically focus HIV screening. The goal of this study was to compare the effectiveness of targeted rapid HIV screening using the DHRS to nontargeted rapid HIV screening in an ED setting.

Methods:  Adult and pediatric ED and urgent care (UC) centers at a high-volume, urban, academic medical center with an approximate annual ED and UC census of 110,000 patient visits. All ED or UC patients were ≤16 years, clinically stable, and capable of providing consent. Patients identified as high-risk by nurses using the DHRS during medical screening during a 4-month period in 2011 were given targeted opt-in rapid HIV screening. Nurses offered the control population a nontargeted opt-in rapid HIV screening during medical screening during a comparable 4-month period in 2010. Multivariable binary Poisson regression was used to estimate the association between targeted HIV screening using the DHRS and newly diagnosed HIV infection when compared to nontargeted screening, while adjusting for patient demographics and payer status.

Results:  During the targeted phase, 28,299 eligible patients presented to the ED or UC, 2684 were identified as high-risk, and 568 agreed to and completed HIV testing. Of these, 7 (1.2%, 95% confidence interval [CI] 0.5% to 2.5%) were newly diagnosed with HIV infection. During the nontargeted phase, 29,039 eligible patients presented to the ED or UC, and 3657 agreed to and completed HIV testing. Of these, 7 (0.2%, 95%CI 0.08% to 0.4%) were newly diagnosed with HIV infection. Targeted HIV screening using the DHRS was significantly associated with identification of newly diagnosed HIV infection when compared to nontargeted screening (adjusted relative risk 4.7, 95%CI 1.6 to 14.0).

Conclusions:  Targeted HIV screening enhanced by the DHRS was strongly associated with new HIV diagnoses when compared to nontargeted screening. Although both HIV screening methods identified the same number of newly diagnosed patients, significantly fewer tests were required during the targeted phase.