Trends in Undiagnosed Chlamydia Prevalence in Baltimore, 1997-1998 and 2006-2009

The 1997-1998 Baltimore STD and Behavior Survey (BSBS) and the 2006-2009 Monitoring STIs Survey Program (MSSP) collected biospecimens from adults ages 18 to 35 in Baltimore to estimate trends in undiagnosed chlamydial infection. The survey recruited a population sample of young adults to participate in an in-person survey of sexual and other sensitive behaviors and STD history. BSBS data collection was conducted over the period of January, 1997 through September, 1998. Respondents also provided a urine sample. The MSSP collected telephone survey data and eligible respondents mailed in specimens for testing. The biospecimens allowed for continuous monitoring of three STIs -- gonorrhea, chlamydial infection, and trichomoniasis. The data collection contains variables about infection symptoms, use of antibiotics, sexual activity and behavior, domestic violence, drug use and whether respondents are positive for chlamydia. Demographic information includes gender, age, education, marital status, race, and employment status.