All ETDs from UAB

Advisory Committee Chair

Sibylle Kristensen

Advisory Committee Members

Alfred Bartolucci

John M Bolland

Mirjam-Colette Kempf

Andrzej Kulczycki

Document Type


Date of Award


Degree Name by School

Doctor of Public Health (DrPH) School of Public Health


Although adolescents in the United States are at high risk of sexually transmitted infections and HIV, research indicates that many do not use condoms consistently and have high numbers of lifetime multiple sexual partners. Among adolescents, different subgroups exhibit distinct patterns of sexual behavior over time. The purpose of this dissertation was to identify trajectories of sexual risk behavior among adolescents and to determine individual, family and community factors that are predictive of membership to trajectory groups. Data were collected on sexual risk behavior among low-income African-American adolescents in Mobile County, Alabama. Gender-balanced subsamples of risky sex (N = 1294) and multiple sexual partners (N =1326) were analyzed. Semiparametric group-based modeling was used to identify the trajectories of risky sex (i.e., condom non-use) and multiple sexual partners from age 10 to 16. Logistic and multinomial logistic regression were used to determine factors that are predictive of trajectory group membership. For risky sex, three distinct trajectories were identified: low, decreasing and increasing-decreasing. When controlled for other variables, male gender and alcohol use predicted trajectory membership. Trajectories of multiple sexual partners were analyzed by gender. Three trajectories emerged among males and two among females. The male trajectories were slowly increasing, fast increasing and high chronic. Alcohol use, forced sexual intercourse and suicidal ideation were significantly associated with membership to trajectory groups, while sense of community barely attained significance. The trajectories identified among females were slowly increasing and fast increasing. None of the factors were predictive of group membership among females. Adolescents exhibit varying sexual risk behavior trajectories. To be more effective in changing behavior, preventive programs should consider heterogeneity, and should tailor strategies according to the long-term behaviors of different subgroups among adolescents. Because experiences early in life may influence sexual behavior in later adolescence, programs should be initiated when adolescents are still young.

Included in

Public Health Commons



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