Document Type



Doctor of Philosophy (PhD)


Public Health

First Advisor's Name

Miguel Ángel Cano

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Mary Jo Trepka

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Tan Li

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Daniel Bagner

Fourth Advisor's Committee Title

Committee member


extended family, coresidence, nuclear family, single-parent, dual-parent, two parent, Add health, family structure, household structure, adolescent, sexual risk behavior, U.S., STI, pregnancy, race, ethnicity, family cohesion, interaction, longitudinal, poisson, ZIP, grandparent

Date of Defense



It is known that dual-parent nuclear households are protective against sexual risk behavior. However, current measures of household structure do not include extended family structure, which has markedly increased over the past sixty years. The growing body of research that does focus on extended family structure largely excludes sexual risk behavior. This study bridges the gap by examining the association between extended family structure and sexual risk behavior.

Responses from 1,386 adolescents who participated in the Add Health study were analyzed. Results showed extended family structure was associated with increased sexual risk behavior for all adolescents, regardless of dual parent status (IRRdual = 2.01, pdual < 0.01, IRRsingle = 1.46, psingle= 0.02). After adjustment, the effect persisted only among those from single-parent households (IRR = 1.45, p = 0.01). Additional findings were that perceived family cohesion moderated the association among adolescents from single-parent households (B = -0.14, p = 0.03). As perceived family cohesion increased, its effect of extended family structure on sexual risk behavior decreased. In the same group, the interaction between race and extended family structure was statistically significant. Upon probing the interaction, while White (IRR = 1.64, B = 0.50, p =

Overall, a higher incidence rate of sexual risk behavior was found among adolescents exposed to extended family structure, particularly in single-parent households. The findings highlight that additional adults in the home may not provide single parents with the functional equivalence of dual-parent households with regard to minimizing sexual risk behavior in their children. Health educators may use this research to inform the design and modification of interventions for sexual risk behavior and offer opportunities to enhance family cohesion. At the policy-level, resources can be allocated towards the preservation of nuclear households.



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