Regression standardized test specificity by month to expiration, adjusting for site, lot, and technician.

<p>The blue squares in the figure represent the mean adjusted specificity of the tests, and the black ovals represent the limits of the 95% bootstrap confidence interval.</p

Multivariable logistic model for false positive test results.

<p>Multivariable logistic model for false positive test results.</p

Test specificity by time to expiration.

<p>Test specificity by time to expiration.</p

Performance of models selected during the development stage (using recent infection as the outcome), here validated using acute HIV infection cases as the outcome.

<p> <b>All models are based on acute HIV infection among persons undergoing HIV testing at the San Francisco City Clinic from 2004–2007 (validation data; n = 12252; excludes recent and longstanding infections).</b></p>1<p><b>Key to checklists:</b> MSM (person is a man who had sex with male partner(s)); IDU (any history of injection drug use); +partner (person had a partner known to be HIV positive); uRAI (engaged in unprotected receptive anal intercourse); STI (had a sexually transmitted infection within the past 2 years or since the last HIV test); AI (engaged in any anal intercourse, regardless of sex or gender); uAI (engaged in unprotected anal intercourse, regardless of sex or gender); RAI (engaged in receptive anal intercourse, regardless of sex or gender); uRAI (engaged in unprotected receptive anal intercourse, regardless of sex or gender).</p

Characteristics, prevalence of longstanding and recent HIV infection, and associations with recent HIV infection among persons undergoing HIV testing at the San Francisco City Clinic from 2004–2007 (development data; n = 12622).

1<p>Longstanding HIV prevalence: prevalence of longstanding infection over the entire study period (2004–2007) (note: recent and acute infections were excluded from the denominator).</p>2<p>Recent HIV prevalence: prevalence of recent infection over the entire study period (2004–2007) (note: acute and longstanding infections were excluded from the denominator).</p>3<p>Age, median (IQR): 32 yrs (26–39).</p>4<p>GLBQQ/Other group includes gay, lesbian, bisexual, queer, “don't know” (questioning), and “other”.</p>5<p>All risk behaviors occurring since time of last HIV test or within the past 2 years, whichever is shorter.</p>6<p>Sexually transmitted infection diagnosed since time of last HIV test or within the past 2 years, whichever is shorter.</p

Performance of various HIV assays with respect to rise and fall of CD4 count, HIV antibodies, HIV viral load, and viral shedding over time after infection.

<p>Black bars to the left of assay names indicate ability of that assay to detect HIV infection.</p

Full multivariable predictive model, and models reduced through backwards selection, for recent HIV infection among persons undergoing HIV testing at the San Francisco City Clinic from 2004–2007 (development data; n = 12350; excludes acute and longstanding infections and n = 3 HIV negative people with missing demographic data).

<p>Full multivariable predictive model, and models reduced through backwards selection, for recent HIV infection among persons undergoing HIV testing at the San Francisco City Clinic from 2004–2007 (development data; n = 12350; excludes acute and longstanding infections and n = 3 HIV negative people with missing demographic data).</p

Performance Characteristics of Four HIV Antibody Screening Tests Used by San Francisco Targeted Testing Programs, 2003–2008.

<p> = rapid test; IA = immunoassay. RT</p

Clinical Testing Algorithm, San Francisco Targeted Testing Programs 2003–2008 (adapted from [6]).

<p>Clinical Testing Algorithm, San Francisco Targeted Testing Programs 2003–2008 (adapted from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0080629#pone.0080629-Patel2" target="_blank">[6]</a>).</p

Identification of Acute (HIV Antibody Negative or Indeterminate) and Established (Confirmed HIV Antibody Positive) HIV Infections by Targeted Testing Programs in San Francisco, 2003–2008.

<p> = rapid test; IA = immunoassay. RT</p><p> Include results from the acute HIV screening program results for years 1998 through 2008.</p