Bonita Iritani, MA¹, Denise Hallfors, PhD¹, Carol A. Ford, MD², Carolyn Tucker Halpern, PhD³, and William C. Miller, MD, PhD, MPH⁴. (1) Pacific Institute for Research and Evaluation, 1516 E. Franklin St., Ste 200., Chapel Hill, NC 27514, 919-265-2611, iritani@pire.org, (2) School of Medicine, Adolescent Medicine Program, Departments of Medicine and Pediatrics, University of North Carolina, CB #7220, Chapel Hill, NC 27599-7220, (3) Dept. of Maternal & Child Health, School of Public Health, University of North Carolina at Chapel Hill, 401 Rosenau Hall, CB# 7445, Chapel Hill, NC 27599-7445, (4) Department of Epidemiology, UNC School of Public Health, CB#7435 McGavran-Greenberg Hall, Chapel Hill, NC 27599-7435

Background: Population-based studies of Chlamydia prevalence often rely on self-reported infection, but self-reports miss infected individuals who are unscreened or asymptomatic. This study uses a population-based sample to (1) assess the prevalence of prior Chlamydia testing, and (2) compare Chlamydia prevalence estimates produced by self-reported infection (diagnosed in the past 12 months) to assay-identified infection. Methods: Data are from Wave 3 of the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative sample of 18-26 year olds in the U.S. (N=14,322). Data include results of Chlamydia urine tests in addition to self-reports of past testing and diagnosis. Testing history, self-reported diagnosis and current test results are examined by biological sex and race-ethnicity. Ratio of assay-identified prevalence to self-report prevalence is calculated as an indicator of difference between the two measures. Results: Prevalence of testing is low; 25% of females and 8% of males were tested in the past year. Self-reported prevalence of a past-year Chlamydia diagnosis is 3% in comparison with a prevalence of 4% for biological test results that indicate infection at one point in time. Differences between self-reported versus assay-identified infection vary by demographic group. Conclusions: This study finds that only a minority of young adults were tested for Chlamydia in the past year and that the ratio of self-reports to assay-identified infections varies by demographic group. Implications regarding the adequacy of current levels of screening will be discussed, as will use of self-reported STI information to determine screening and/or STI prevention needs.

Learning Objectives:

• Identify level of Chlamydia testing among young adults in the U.S.
• Describe the prevalence of Chlamydia identified by 12-month self-reports versus test results.
• Discuss how differences between Chlamydia self-reports and test results vary by demographic group.

Keywords: STD, Data/Surveillance

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.