Carolyn Halpern - Academia.edu (original) (raw)

Papers by Carolyn Halpern

Applied statistics, Apr 2, 2019

Research Square (Research Square), May 22, 2023

Women with disabilities face a number of barriers when accessing reproductive health services, in... more Women with disabilities face a number of barriers when accessing reproductive health services, including maternal healthcare. These include physical inaccessibility, costs, transportation, negative attitudes from family and healthcare providers, and a societal belief people with disabilities shouldn't be parents. While qualitative studies have uncovered these barriers, there is limited quantitative research to determine their impact on use of maternal health services. This study aims to analyze associations between disability and maternal healthcare use among married women in Rajasthan. This study is a secondary analysis of the Indian Annual Heath Survey rst wave data from 2011. The sample includes 141,983 women aged 15-49 who had given birth between 2007 and 2009. Logistic regression was used to assess the association between disability and use of antenatal, delivery, and postnatal care. Strati ed models were created to analyze difference based on birth order of the pregnancy and whether the woman's place of residence is rural or urban. The prevalence of disability was 1.23%. Attending at least three antenatal care visits was reported by 50.66% of the sample, skilled delivery use by 83.81%, and receiving postnatal care within 48 hours of birth by 76.02%. In the regression model, women with disabilities were less likely to report attending the minimum antenatal care visits (OR = 0.84; CI: 0.76, 0.92). No association was found between disability and skilled delivery or postnatal care. Once the sample was strati ed by birth order, women with disabilities reporting their rst birth were more likely to report receiving postnatal care than women without disabilities (OR = 1.47; CI: 1.13, 1.91). Additional research is needed to determine use of maternal healthcare among women with disabilities in India. Maternal services need to be assessed to determine their accessibility, especially regarding recent laws requiring accessibility.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2017

Cash transfer programmes have recently emerged as promising interventions for HIV prevention amon... more Cash transfer programmes have recently emerged as promising interventions for HIV prevention among adolescents in Africa. However, the pathways through which risk reduction occurs are not well understood. We examine data on 1429 adolescents and youth from the Kenya Cash Transfer for Orphans and Vulnerable Children, which has been shown to result in delayed sexual debut among adolescents. We explored three potential mediating pathways: schooling, socioeconomic status and psychosocial status. None of these hypothesised mediators greatly altered the main effect. However, school attendance had a larger protective effect on sexual debut among females but was only increased by the programme among males. This gendered pattern of effects may explain why we did not see a mediating effect of the cash transfer through schooling, despite schooling's protective effects against early sexual debut. Results also suggest that cash transfer programmes in Africa can contribute to the reduction of HIV related risk behaviours.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2017

Introduction-There is limited research on rapid repeat pregnancies (RRP) among adolescents, espec... more Introduction-There is limited research on rapid repeat pregnancies (RRP) among adolescents, especially using nationally representative samples. We examine distal factors-school, family, peers, and public/private religious ties-and their associations with RRP among adolescent mothers. Methods-Guided by social development theory, we conducted multivariate logistic regression analyses, adjusted for sociodemographic characteristics, to examine associations between RRP and attachment to school, family, peers, and religion among 1,158 female respondents from the National Longitudinal Study of Adolescent to Adult Health (Add Health) who reported at least one live birth before age 20. Results-Attachments to conventional institutions were associated with lower likelihood of RRP. Adolescent mothers who had a stronger relationship with their parents had reduced odds of RRP (adjusted odds ratio [aOR] 0.83, 95% CI 0.71-0.99). Increased odds of RRP were associated with anticipating fewer negative social consequences of sex (aOR 1.18, 95% CI 1.02-1.35), never praying (versus praying daily; aOR 1.47, 95% CI 1.10-1.96), and never participating in churchrelated youth activities (versus participating once a week; 1.04, 95% CI 1.01-1.07). Discussion-After an adolescent birth, social support from family, peers, and the community can benefit young mothers. Private aspects of religiosity may be especially important. Understanding the processes by which these distal factors are linked to the likelihood of RRP is needed to create multifaceted intervention programs that provide diverse methods of support customized to specific circumstances of adolescent mothers.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2016

Purpose-Both substance use and depression are common in adolescence and often comorbid. Past rese... more Purpose-Both substance use and depression are common in adolescence and often comorbid. Past research has produced conflicting results on whether there is a temporal relationship and if so, in which direction it operates and how it may vary by sex. The purpose of this paper is to explore the longitudinal, potentially bidirectional, relationships between high-frequency substance use and depressive symptoms from adolescence into young adulthood for males and females. Methods-Using data from the National Longitudinal Study of Adolescent to Adult Health we investigated longitudinal associations between high frequency substance use (alcohol, cigarettes, and marijuana) and depressive symptoms. The linear mixed effects models were stratified by sex and used a lagged measure of the dependent variable to test temporal relationships. A random intercept was used for respondent ID. Results-Increases in depressive symptoms were significantly associated with a later increase of about a half day in marijuana use frequency for males and nearly a two day increase in smoking frequency for females. Conversely, increases in smoking frequency were significantly associated with approximately a 0.6-point increase for females and 0.4-point increase for males in depressive symptoms at a later wave. indicate a bidirectional relationship between smoking and depressive symptoms for females. For males, there was evidence supporting self-medication with marijuana and for smoking being associated with later increases in depressive symptoms. Results inform how substance use and depression screening, prevention and treatment efforts should be paired and targeted for males and females.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2016

Purpose-This study investigates the causal effect of Kenya's unconditional cash transfer program ... more Purpose-This study investigates the causal effect of Kenya's unconditional cash transfer program on mental health outcomes of young people. Locations in Kenya were randomly assigned to receive unconditional cash transfers in the first phase of Kenya's Cash Transfer Program for Orphans and Vulnerable Children (CT-OVC). In intervention Locations, low-income households and those with OVCs began receiving monthly cash transfers of $20 in 2007. In 2011, four years after program onset, data were collected on the psychosocial status for youth aged 15-24 from households in intervention and control Locations (N=1960). The primary outcome variable was an indicator of depressive symptoms using the 10-question Center for Epidemiologic Studies Depression Scale (CES-D10). Secondary outcomes include Hope and physical health measures. Logistic regression models that adjusted for individual and household characteristics were used to determine the effect of the cash transfer program.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2019

Background: Sexual partners are the primary source of incident HIV infection among adolescent gir... more Background: Sexual partners are the primary source of incident HIV infection among adolescent girls and young women (AGYW) in sub-Saharan Africa. Identifying partner types at greatest risk of HIV transmission could guide the design of tailored HIV prevention interventions. We conducted a secondary analysis of data from AGYW (aged 13-23 years) enrolled in a randomized controlled trial of cash transfers for HIV prevention in South Africa. Annually, AGYW reported behavioral and demographic characteristics of their 3 most recent sexual partners, categorized each partner using prespecified labels, and received HIV testing. We used latent class analysis (LCA) to identify partner types from reported characteristics, and generalized estimating equations to estimate the relationship between both LCAidentified and prespecified partner types and incident HIV infection. Results: Across 2140 AGYW visits, 1034 AGYW made 2968 partner reports and 63 AGYW acquired HIV infection. We identified 5 LCA partner types, which we named monogamous HIV-negative peer partner; one-time protected in-school peer partner; out-ofschool older partner; anonymous out-of-school peer partner; and cohabiting with children in-school peer partner. Compared to AGYW with only monogamous HIV-negative peer partners, AGYW with out-of-school older partners had 2.56 times the annual risk of HIV infection (95% confidence interval: 1.23 to 5.33), whereas AGYW with anonymous out-of-school peer partners had 1.72 times the risk (95% confidence interval: 0.82 to 3.59). Prespecified partner types were not associated with incident HIV. By identifying meaningful combinations of partner characteristics and predicting the corresponding risk of HIV acquisition among AGYW, LCA-identified partner types may provide new insights for the design of tailored HIV prevention interventions.

International Journal of Obesity, Sep 11, 2018

Background: A single measure that distills complex body mass index (BMI) trajectories into one va... more Background: A single measure that distills complex body mass index (BMI) trajectories into one value could facilitate otherwise complicated analyses. This study creates and assesses the validity of such a measure: average excess BMI. We use data from Waves I-IV of the National Longitudinal Study of Adolescent to Adult Health (n=17 669). We calculate average excess BMI by integrating to find the area above a healthy BMI trajectory and below each subject-specific trajectory and divide this value by total study time. To assess validity and utility, we (1) evaluate relationships between average excess BMI from adolescence to adulthood and adult chronic conditions, (2) compare associations and fit to models using subject-specific BMI trajectory parameter estimates as predictors, and (3) compare associations to models using BMI trajectory parameter estimates as outcomes. Results: Average excess BMI from adolescence to adulthood is associated with increased odds of hypertension (OR = 1.56; 95% CI: 1.47, 1.67), hyperlipidemia (OR = 1.36; 95% CI: 1.26, 1.47), and diabetes (OR = 1.57; 95% CI: 1.47, 1.67). The odds associated with average excess BMI are higher than the odds associated with the BMI intercept, linear, or quadratic slope. Correlations between observed and predicted health outcomes are slightly lower for some models using average excess BMI as the focal predictor compared to those using BMI intercept, linear, and quadratic slope. When using trajectory parameters as outcomes, some covariates associate with the intercept, linear, and quadratic slope in contradicting directions. This study supports the utility of average excess BMI as an outcome. The higher an individual's average excess BMI from adolescence to adulthood, the greater their odds of chronic conditions. Future studies investigating longitudinal BMI as an outcome should consider using average excess BMI, whereas studies that conceptualize longitudinal BMI as the predictor should continue using traditional latent growth methods. Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

National symposium on family issues, Oct 15, 2013

This chapter discusses biological measures as contributors to the family system and biomarker col... more This chapter discusses biological measures as contributors to the family system and biomarker collection in large scale studies, framed primarily through our experiences in the National Longitudinal Study of Adolescent Health (Add Health). We illustrate field, laboratory, and data dissemination challenges for a selection of common biomarkers, leading to best practice recommendations. We also present illustrative findings of multilevel systems research integrating biomarker, social, and behavioral data that provide novel insights into social and behavioral phenomena. We close with a rationale for incorporating biomarkers into social science research, despite the challenges, and highlight future possibilities for expanded multilevel systems research capitalizing on intergenerational study designs.

Fertility and Sterility, Oct 1, 2019

Objective: To provide national estimates of donor insemination (DI) use in the United States and ... more Objective: To provide national estimates of donor insemination (DI) use in the United States and a description of the population of users. Design: Population estimates were generated from nationally representative data through weighted proportions and count estimates. Setting: Not applicable. Patient(s): Participants were U.S. women of childbearing age (15-44 years) sampled for interview in the National Survey of Family Growth. Intervention(s): None. Main Outcome Measure(s): Respondents who reported having received artificial insemination were asked the origin of the sperm. Responses could include husband/partner, donor only, or mixed donor and husband/partner. Result(s): In 1995, an estimated 170,701 (95% confidence interval 106,577-234,825) women had undergone DI using donor or mixed sperm. In 2015-2017, 440,986 (95% confidence interval 108,458-773,513) women were estimated to have used it. The DI users were mostly white, urban, older, college-educated, and had high family incomes. The DI use changed over time, from a decrease between 1995 and 2013 to a precipitous growth in 2015 to 2017. In recent years, nearly half a million women may be dealing with personal, relationship, and familial issues born of DI use. The United States does not maintain records on the usage of donor sperm, but better tracking of the use and outcomes of treatment would provide better estimates of the size of the affected population. (Fertil Steril Ò 2019;112:718-23. Ó2019 by American Society for Reproductive Medicine.) El resumen está disponible en Español al final del artículo.

Children and Youth Services Review, Oct 1, 2018

This study examines the relationship between childhood maltreatment experiences and body mass ind... more This study examines the relationship between childhood maltreatment experiences and body mass index (BMI) over time. Using data from the National Longitudinal Study of Adolescent to Adult Health, we use latent profile analysis to create child maltreatment experience classes and latent growth modeling to understand how classes relate to BMI trajectories from adolescence to early adulthood. The best-fitting model suggests four child maltreatment experience classes: 1) polymaltreatment (n=607); 2) physical abuse (n=1,578); 3) physical abuse and neglect (n=345); and 4) no childhood maltreatment (n=4,188). Class membership differentially predicts BMI trajectories, such that individuals in the no maltreatment, physical abuse, and physical abuse plus neglect classes exhibit the most stable BMI, and individuals in the poly-maltreatment class increase most rapidly (Χ 2 [9]=149.9, p < 0.001). Individuals in the poly-maltreatment class experience significantly higher BMI over time compared to the other three classes. In addition to overall growth differing between classes, there is substantial inter-individual variability in BMI trajectories within each class. Because BMI trajectories differ across different childhood maltreatment experiences-and substantial variability in BMI trajectories exists within these different experiences-future analyses should investigate mediators and moderators of this relationship to inform trauma-based therapies and interventions.

Perspectives on Sexual and Reproductive Health, Mar 1, 2017

CONTEXT: Holistic examinations of sexual initiation are needed to understand implications for lat... more CONTEXT: Holistic examinations of sexual initiation are needed to understand implications for later sexual health; such examinations are not available for gay, lesbian, and bisexual sexual minorities [SM]. Separate latent class analysis (LCA) identified patterns of sexual initiation among 1,628 SM females and 528 SM males in the National Longitudinal Study of Adolescent to Adult Health, Wave IV (2008), accounting for timing, sequence, and spacing of first oral, anal, and vaginal sexual encounter. Multinomial logistic regression assessed sociodemographic predictors of class membership. RESULTS: SM female sexual initiation classes were characterized as 'typical debut' (41%; vaginal intercourse debut and short spacing between debut and second behavior); 'dual-behavior debut' (35%; oral sex + vaginal intercourse debut in same year); 'early sexual debut' (17%); and 'delayed debut with oral sex,' (6%). SM male sexual initiation was characterized as 'single behavior debut' (50%; oral sex initiation and long spacing between 1 st and 2 nd behaviors); 'multibehavior debut' (32%; largely oral sex + vaginal intercourse in same year); 'early anal sex' (11%); and 'very early debut' (6%). Class membership was predicted by sociodemographic characteristics, including race/ethnicity, SES (females only), religiosity, and sexual victimization (males only). Sexual initiation patterns of sexual minority adolescents reflect non-coital behaviors and characteristics beyond timing, yet current measures do not capture this variety. Researchers should consider adopting sexual initiation measures specific to SM populations.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2021

This work investigates the associations between experiences of domestic minor sex trafficking and... more This work investigates the associations between experiences of domestic minor sex trafficking and adolescent interpersonal violence victimizations, including intimate partner violence (IPV) and community violence. Abuse and violence in childhood are commonly proposed as risk factors for domestic minor sex trafficking. However, less is known about how interpersonal violence victimizations in adolescence connect to domestic minor sex trafficking experiences. The poly-victimization framework provides a means to understand domestic minor sex trafficking as a type of violence amid a web of additional interconnected violence victimizations. Efforts to better understand the interpersonal violence experienced by survivors of domestic minor sex trafficking are valuable in contextualizing trafficking experiences for adolescents. Data from The National Longitudinal Study of Adolescent to Adult Health, a population-based sample of adolescents in the United States ( n = 12,605) were used to examine experiences of domestic minor sex trafficking for minor respondents, as measured through

Contraception, Dec 1, 2018

Statistics & Probability Letters, Jun 1, 2016

In population studies, it is standard to sample data via designs in which the population is divid... more In population studies, it is standard to sample data via designs in which the population is divided into strata, with the different strata assigned different probabilities of inclusion. Although there have been some proposals for including sample survey weights into Bayesian analyses, existing methods require complex models or ignore the stratified design underlying the survey weights. We propose a simple approach based on modeling the distribution of the selected sample as a mixture, with the mixture weights appropriately adjusted, while accounting for uncertainty in the adjustment. We focus for simplicity on Dirichlet process mixtures but the proposed approach can be applied more broadly. We sketch a simple Markov chain Monte Carlo algorithm for computation, and assess the approach via simulations and an application.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2013

This article describes the design and phenotype and genotype data available for sibling pairs wit... more This article describes the design and phenotype and genotype data available for sibling pairs with varying genetic relatedness in the National Longitudinal Study of Adolescent Health (Add Health). Add Health is a nationally-representative longitudinal study of over 20,000 adolescents in the U.S. in 1994-95 who have been followed for fifteen years into adulthood. The Add Health design included oversamples of more than 3,000 pairs of individuals with varying genetic resemblance, ranging from monozygotic twins, dizygotic twins, full siblings, half siblings, and unrelated siblings who were raised in the same household. Add Health sibling pairs are therefore nationally representative and followed longitudinally from early adolescence into adulthood with 4 in-home interviews during the period 1994-2009. Add Health has collected rich longitudinal social, behavioral, environmental, and biological data, as well as buccal cell DNA from all sample members, including siblings pairs. Add Health has an enlightened dissemination policy and to date has released phenotype and genotype data to more than 10,000 researchers in the scientific community.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2009

This study aimed to examine perceptual factors associated with condom use, and the relationship b... more This study aimed to examine perceptual factors associated with condom use, and the relationship between condom use and the timing of sexual debut, among male secondary-school students in Nairobi, Kenya. Data are from the TeenWeb study, a school-based project that used the World Wide Web to assess the health needs of secondary-school students, and tested the web's utility as a teaching and research modality. Analyses are based on 214 sexually experienced males aged 14 to 20 years who completed web-based questionnaires about their sexual attitudes and behaviour. Results indicate that students did not see themselves as susceptible to HIV/AIDS and believed condom effectiveness in preventing HIV to be low. Consequently, only a marginal association was found between agreeing that buying condoms is embarrassing and condom use at first sexual intercourse. However, contrary to expectation, agreeing that condoms often break (almost half of participants) was associated with a higher likelihood of condom use at first sex. Each year of delay in sexual debut increased the likelihood of using a condom at first sex by 1.44 times. In turn, having used a condom at first sex increased the likelihood of using one at the most recent sex by 4.81 times, and elevated general condom use ("most or all the time") by 8.76 times. Interventions to increase awareness about the role of condoms in preventing HIV, delay sexual initiation, and teach proper condom use among secondary-school students in Nairobi are needed.

Journal of Epidemiology and Community Health, Sep 6, 2018

Journal of Research on Adolescence, Apr 9, 2010

A theoretical model of gender differences in depressive symptoms during adolescence was evaluated... more A theoretical model of gender differences in depressive symptoms during adolescence was evaluated using data from Waves I and II of the National Longitudinal Study of Adolescent Health. The theoretical model under examination was primarily informed by the gender-additive model of gender differences in depressive symptoms during adolescence proposed by . In the model, it was posited that BMI would be associated with perceiving oneself as overweight, which would then lead to a higher probability of dieting, which would be associated with greater depressive symptoms. Participants were 10,864 male and female adolescents. Gender did not moderate any of the model pathways, but mediation analysis indicated that gender differences in changes in depressive symptoms were mediated by perceived weight status and dieting. Findings suggest that one explanation for girls' higher depressive symptoms in adolescence relative to boys is girls' greater tendencies to perceive themselves as overweight and to diet. Depression affects women at a rate twice as high as that observed among men . Before adolescence, depressed males may actually outnumber their female peers, but at approximately age 13 or 14, depression becomes more prevalent among females than males . Studies using continuous, self-report measures of depressive symptoms have found that girls begin to evidence significantly higher mean levels of depressive symptoms relative to boys at the age of 13 or 14 . This pattern has been supported by meta-analysis . Efforts to explain gender differences in depression during adolescence typically have examined suspected risk factors for depression (e.g., rumination, communion, body dissatisfaction, stressful events) individually as mediators of gender differences in depression or have examined gender as a moderator of the relationship between the risk factor and depression . Conceptually, mediation of the relationship between two variables occurs when the effect of one variable on the other is exerted through an intervening variable . Mediation models of gender differences in depression therefore capture the extent to which the effect of gender on depression is transmitted through a given variable or mediator.

Inter-temporal choice represents one of the most fascinating topics in economics. Understanding i... more Inter-temporal choice represents one of the most fascinating topics in economics. Understanding its determinants can provide vital insight into decisions ranging from savings and financial investment to smoking, obesity and human capital accumulation. This article contributes to a growing literature that seeks to identify the determinants of inter-temporal choice. We explore the role of income shocks, age and gender on time discounting using evaluation data from the Government of Kenya's largest social protection programme, the Kenya Cash Transfer for Orphans and Vulnerable Children (CT-OVC). Study participants were randomised to treatment and control arms in 2007 and data on time discounting was collected on participants four years after programme inception. Our paper confirms that middle-aged groups are more patient than younger and older adults. In contrast to the empirical evidence, females are less patient than males and this situation is more evident during young and adult life. Males lose their patient during old age. Considering the impact of the programme, the average treatment effect of the programme on time discounting is negligible. However, it varies strongly with age of the recipient, with large and statistically significant effects among prime-age recipients and no effects on younger or older recipients. Moreover, these results are stronger for females than males, an important result given that over 60 per cent of recipients in target households are females.

Applied statistics, Apr 2, 2019

Research Square (Research Square), May 22, 2023

Women with disabilities face a number of barriers when accessing reproductive health services, in... more Women with disabilities face a number of barriers when accessing reproductive health services, including maternal healthcare. These include physical inaccessibility, costs, transportation, negative attitudes from family and healthcare providers, and a societal belief people with disabilities shouldn't be parents. While qualitative studies have uncovered these barriers, there is limited quantitative research to determine their impact on use of maternal health services. This study aims to analyze associations between disability and maternal healthcare use among married women in Rajasthan. This study is a secondary analysis of the Indian Annual Heath Survey rst wave data from 2011. The sample includes 141,983 women aged 15-49 who had given birth between 2007 and 2009. Logistic regression was used to assess the association between disability and use of antenatal, delivery, and postnatal care. Strati ed models were created to analyze difference based on birth order of the pregnancy and whether the woman's place of residence is rural or urban. The prevalence of disability was 1.23%. Attending at least three antenatal care visits was reported by 50.66% of the sample, skilled delivery use by 83.81%, and receiving postnatal care within 48 hours of birth by 76.02%. In the regression model, women with disabilities were less likely to report attending the minimum antenatal care visits (OR = 0.84; CI: 0.76, 0.92). No association was found between disability and skilled delivery or postnatal care. Once the sample was strati ed by birth order, women with disabilities reporting their rst birth were more likely to report receiving postnatal care than women without disabilities (OR = 1.47; CI: 1.13, 1.91). Additional research is needed to determine use of maternal healthcare among women with disabilities in India. Maternal services need to be assessed to determine their accessibility, especially regarding recent laws requiring accessibility.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2017

Cash transfer programmes have recently emerged as promising interventions for HIV prevention amon... more Cash transfer programmes have recently emerged as promising interventions for HIV prevention among adolescents in Africa. However, the pathways through which risk reduction occurs are not well understood. We examine data on 1429 adolescents and youth from the Kenya Cash Transfer for Orphans and Vulnerable Children, which has been shown to result in delayed sexual debut among adolescents. We explored three potential mediating pathways: schooling, socioeconomic status and psychosocial status. None of these hypothesised mediators greatly altered the main effect. However, school attendance had a larger protective effect on sexual debut among females but was only increased by the programme among males. This gendered pattern of effects may explain why we did not see a mediating effect of the cash transfer through schooling, despite schooling's protective effects against early sexual debut. Results also suggest that cash transfer programmes in Africa can contribute to the reduction of HIV related risk behaviours.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2017

Introduction-There is limited research on rapid repeat pregnancies (RRP) among adolescents, espec... more Introduction-There is limited research on rapid repeat pregnancies (RRP) among adolescents, especially using nationally representative samples. We examine distal factors-school, family, peers, and public/private religious ties-and their associations with RRP among adolescent mothers. Methods-Guided by social development theory, we conducted multivariate logistic regression analyses, adjusted for sociodemographic characteristics, to examine associations between RRP and attachment to school, family, peers, and religion among 1,158 female respondents from the National Longitudinal Study of Adolescent to Adult Health (Add Health) who reported at least one live birth before age 20. Results-Attachments to conventional institutions were associated with lower likelihood of RRP. Adolescent mothers who had a stronger relationship with their parents had reduced odds of RRP (adjusted odds ratio [aOR] 0.83, 95% CI 0.71-0.99). Increased odds of RRP were associated with anticipating fewer negative social consequences of sex (aOR 1.18, 95% CI 1.02-1.35), never praying (versus praying daily; aOR 1.47, 95% CI 1.10-1.96), and never participating in churchrelated youth activities (versus participating once a week; 1.04, 95% CI 1.01-1.07). Discussion-After an adolescent birth, social support from family, peers, and the community can benefit young mothers. Private aspects of religiosity may be especially important. Understanding the processes by which these distal factors are linked to the likelihood of RRP is needed to create multifaceted intervention programs that provide diverse methods of support customized to specific circumstances of adolescent mothers.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2016

Purpose-Both substance use and depression are common in adolescence and often comorbid. Past rese... more Purpose-Both substance use and depression are common in adolescence and often comorbid. Past research has produced conflicting results on whether there is a temporal relationship and if so, in which direction it operates and how it may vary by sex. The purpose of this paper is to explore the longitudinal, potentially bidirectional, relationships between high-frequency substance use and depressive symptoms from adolescence into young adulthood for males and females. Methods-Using data from the National Longitudinal Study of Adolescent to Adult Health we investigated longitudinal associations between high frequency substance use (alcohol, cigarettes, and marijuana) and depressive symptoms. The linear mixed effects models were stratified by sex and used a lagged measure of the dependent variable to test temporal relationships. A random intercept was used for respondent ID. Results-Increases in depressive symptoms were significantly associated with a later increase of about a half day in marijuana use frequency for males and nearly a two day increase in smoking frequency for females. Conversely, increases in smoking frequency were significantly associated with approximately a 0.6-point increase for females and 0.4-point increase for males in depressive symptoms at a later wave. indicate a bidirectional relationship between smoking and depressive symptoms for females. For males, there was evidence supporting self-medication with marijuana and for smoking being associated with later increases in depressive symptoms. Results inform how substance use and depression screening, prevention and treatment efforts should be paired and targeted for males and females.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2016

Purpose-This study investigates the causal effect of Kenya's unconditional cash transfer program ... more Purpose-This study investigates the causal effect of Kenya's unconditional cash transfer program on mental health outcomes of young people. Locations in Kenya were randomly assigned to receive unconditional cash transfers in the first phase of Kenya's Cash Transfer Program for Orphans and Vulnerable Children (CT-OVC). In intervention Locations, low-income households and those with OVCs began receiving monthly cash transfers of $20 in 2007. In 2011, four years after program onset, data were collected on the psychosocial status for youth aged 15-24 from households in intervention and control Locations (N=1960). The primary outcome variable was an indicator of depressive symptoms using the 10-question Center for Epidemiologic Studies Depression Scale (CES-D10). Secondary outcomes include Hope and physical health measures. Logistic regression models that adjusted for individual and household characteristics were used to determine the effect of the cash transfer program.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2019

Background: Sexual partners are the primary source of incident HIV infection among adolescent gir... more Background: Sexual partners are the primary source of incident HIV infection among adolescent girls and young women (AGYW) in sub-Saharan Africa. Identifying partner types at greatest risk of HIV transmission could guide the design of tailored HIV prevention interventions. We conducted a secondary analysis of data from AGYW (aged 13-23 years) enrolled in a randomized controlled trial of cash transfers for HIV prevention in South Africa. Annually, AGYW reported behavioral and demographic characteristics of their 3 most recent sexual partners, categorized each partner using prespecified labels, and received HIV testing. We used latent class analysis (LCA) to identify partner types from reported characteristics, and generalized estimating equations to estimate the relationship between both LCAidentified and prespecified partner types and incident HIV infection. Results: Across 2140 AGYW visits, 1034 AGYW made 2968 partner reports and 63 AGYW acquired HIV infection. We identified 5 LCA partner types, which we named monogamous HIV-negative peer partner; one-time protected in-school peer partner; out-ofschool older partner; anonymous out-of-school peer partner; and cohabiting with children in-school peer partner. Compared to AGYW with only monogamous HIV-negative peer partners, AGYW with out-of-school older partners had 2.56 times the annual risk of HIV infection (95% confidence interval: 1.23 to 5.33), whereas AGYW with anonymous out-of-school peer partners had 1.72 times the risk (95% confidence interval: 0.82 to 3.59). Prespecified partner types were not associated with incident HIV. By identifying meaningful combinations of partner characteristics and predicting the corresponding risk of HIV acquisition among AGYW, LCA-identified partner types may provide new insights for the design of tailored HIV prevention interventions.

International Journal of Obesity, Sep 11, 2018

Background: A single measure that distills complex body mass index (BMI) trajectories into one va... more Background: A single measure that distills complex body mass index (BMI) trajectories into one value could facilitate otherwise complicated analyses. This study creates and assesses the validity of such a measure: average excess BMI. We use data from Waves I-IV of the National Longitudinal Study of Adolescent to Adult Health (n=17 669). We calculate average excess BMI by integrating to find the area above a healthy BMI trajectory and below each subject-specific trajectory and divide this value by total study time. To assess validity and utility, we (1) evaluate relationships between average excess BMI from adolescence to adulthood and adult chronic conditions, (2) compare associations and fit to models using subject-specific BMI trajectory parameter estimates as predictors, and (3) compare associations to models using BMI trajectory parameter estimates as outcomes. Results: Average excess BMI from adolescence to adulthood is associated with increased odds of hypertension (OR = 1.56; 95% CI: 1.47, 1.67), hyperlipidemia (OR = 1.36; 95% CI: 1.26, 1.47), and diabetes (OR = 1.57; 95% CI: 1.47, 1.67). The odds associated with average excess BMI are higher than the odds associated with the BMI intercept, linear, or quadratic slope. Correlations between observed and predicted health outcomes are slightly lower for some models using average excess BMI as the focal predictor compared to those using BMI intercept, linear, and quadratic slope. When using trajectory parameters as outcomes, some covariates associate with the intercept, linear, and quadratic slope in contradicting directions. This study supports the utility of average excess BMI as an outcome. The higher an individual's average excess BMI from adolescence to adulthood, the greater their odds of chronic conditions. Future studies investigating longitudinal BMI as an outcome should consider using average excess BMI, whereas studies that conceptualize longitudinal BMI as the predictor should continue using traditional latent growth methods. Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

National symposium on family issues, Oct 15, 2013

This chapter discusses biological measures as contributors to the family system and biomarker col... more This chapter discusses biological measures as contributors to the family system and biomarker collection in large scale studies, framed primarily through our experiences in the National Longitudinal Study of Adolescent Health (Add Health). We illustrate field, laboratory, and data dissemination challenges for a selection of common biomarkers, leading to best practice recommendations. We also present illustrative findings of multilevel systems research integrating biomarker, social, and behavioral data that provide novel insights into social and behavioral phenomena. We close with a rationale for incorporating biomarkers into social science research, despite the challenges, and highlight future possibilities for expanded multilevel systems research capitalizing on intergenerational study designs.

Fertility and Sterility, Oct 1, 2019

Objective: To provide national estimates of donor insemination (DI) use in the United States and ... more Objective: To provide national estimates of donor insemination (DI) use in the United States and a description of the population of users. Design: Population estimates were generated from nationally representative data through weighted proportions and count estimates. Setting: Not applicable. Patient(s): Participants were U.S. women of childbearing age (15-44 years) sampled for interview in the National Survey of Family Growth. Intervention(s): None. Main Outcome Measure(s): Respondents who reported having received artificial insemination were asked the origin of the sperm. Responses could include husband/partner, donor only, or mixed donor and husband/partner. Result(s): In 1995, an estimated 170,701 (95% confidence interval 106,577-234,825) women had undergone DI using donor or mixed sperm. In 2015-2017, 440,986 (95% confidence interval 108,458-773,513) women were estimated to have used it. The DI users were mostly white, urban, older, college-educated, and had high family incomes. The DI use changed over time, from a decrease between 1995 and 2013 to a precipitous growth in 2015 to 2017. In recent years, nearly half a million women may be dealing with personal, relationship, and familial issues born of DI use. The United States does not maintain records on the usage of donor sperm, but better tracking of the use and outcomes of treatment would provide better estimates of the size of the affected population. (Fertil Steril Ò 2019;112:718-23. Ó2019 by American Society for Reproductive Medicine.) El resumen está disponible en Español al final del artículo.

Children and Youth Services Review, Oct 1, 2018

This study examines the relationship between childhood maltreatment experiences and body mass ind... more This study examines the relationship between childhood maltreatment experiences and body mass index (BMI) over time. Using data from the National Longitudinal Study of Adolescent to Adult Health, we use latent profile analysis to create child maltreatment experience classes and latent growth modeling to understand how classes relate to BMI trajectories from adolescence to early adulthood. The best-fitting model suggests four child maltreatment experience classes: 1) polymaltreatment (n=607); 2) physical abuse (n=1,578); 3) physical abuse and neglect (n=345); and 4) no childhood maltreatment (n=4,188). Class membership differentially predicts BMI trajectories, such that individuals in the no maltreatment, physical abuse, and physical abuse plus neglect classes exhibit the most stable BMI, and individuals in the poly-maltreatment class increase most rapidly (Χ 2 [9]=149.9, p < 0.001). Individuals in the poly-maltreatment class experience significantly higher BMI over time compared to the other three classes. In addition to overall growth differing between classes, there is substantial inter-individual variability in BMI trajectories within each class. Because BMI trajectories differ across different childhood maltreatment experiences-and substantial variability in BMI trajectories exists within these different experiences-future analyses should investigate mediators and moderators of this relationship to inform trauma-based therapies and interventions.

Perspectives on Sexual and Reproductive Health, Mar 1, 2017

CONTEXT: Holistic examinations of sexual initiation are needed to understand implications for lat... more CONTEXT: Holistic examinations of sexual initiation are needed to understand implications for later sexual health; such examinations are not available for gay, lesbian, and bisexual sexual minorities [SM]. Separate latent class analysis (LCA) identified patterns of sexual initiation among 1,628 SM females and 528 SM males in the National Longitudinal Study of Adolescent to Adult Health, Wave IV (2008), accounting for timing, sequence, and spacing of first oral, anal, and vaginal sexual encounter. Multinomial logistic regression assessed sociodemographic predictors of class membership. RESULTS: SM female sexual initiation classes were characterized as 'typical debut' (41%; vaginal intercourse debut and short spacing between debut and second behavior); 'dual-behavior debut' (35%; oral sex + vaginal intercourse debut in same year); 'early sexual debut' (17%); and 'delayed debut with oral sex,' (6%). SM male sexual initiation was characterized as 'single behavior debut' (50%; oral sex initiation and long spacing between 1 st and 2 nd behaviors); 'multibehavior debut' (32%; largely oral sex + vaginal intercourse in same year); 'early anal sex' (11%); and 'very early debut' (6%). Class membership was predicted by sociodemographic characteristics, including race/ethnicity, SES (females only), religiosity, and sexual victimization (males only). Sexual initiation patterns of sexual minority adolescents reflect non-coital behaviors and characteristics beyond timing, yet current measures do not capture this variety. Researchers should consider adopting sexual initiation measures specific to SM populations.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2021

This work investigates the associations between experiences of domestic minor sex trafficking and... more This work investigates the associations between experiences of domestic minor sex trafficking and adolescent interpersonal violence victimizations, including intimate partner violence (IPV) and community violence. Abuse and violence in childhood are commonly proposed as risk factors for domestic minor sex trafficking. However, less is known about how interpersonal violence victimizations in adolescence connect to domestic minor sex trafficking experiences. The poly-victimization framework provides a means to understand domestic minor sex trafficking as a type of violence amid a web of additional interconnected violence victimizations. Efforts to better understand the interpersonal violence experienced by survivors of domestic minor sex trafficking are valuable in contextualizing trafficking experiences for adolescents. Data from The National Longitudinal Study of Adolescent to Adult Health, a population-based sample of adolescents in the United States ( n = 12,605) were used to examine experiences of domestic minor sex trafficking for minor respondents, as measured through

Contraception, Dec 1, 2018

Statistics & Probability Letters, Jun 1, 2016

In population studies, it is standard to sample data via designs in which the population is divid... more In population studies, it is standard to sample data via designs in which the population is divided into strata, with the different strata assigned different probabilities of inclusion. Although there have been some proposals for including sample survey weights into Bayesian analyses, existing methods require complex models or ignore the stratified design underlying the survey weights. We propose a simple approach based on modeling the distribution of the selected sample as a mixture, with the mixture weights appropriately adjusted, while accounting for uncertainty in the adjustment. We focus for simplicity on Dirichlet process mixtures but the proposed approach can be applied more broadly. We sketch a simple Markov chain Monte Carlo algorithm for computation, and assess the approach via simulations and an application.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2013

This article describes the design and phenotype and genotype data available for sibling pairs wit... more This article describes the design and phenotype and genotype data available for sibling pairs with varying genetic relatedness in the National Longitudinal Study of Adolescent Health (Add Health). Add Health is a nationally-representative longitudinal study of over 20,000 adolescents in the U.S. in 1994-95 who have been followed for fifteen years into adulthood. The Add Health design included oversamples of more than 3,000 pairs of individuals with varying genetic resemblance, ranging from monozygotic twins, dizygotic twins, full siblings, half siblings, and unrelated siblings who were raised in the same household. Add Health sibling pairs are therefore nationally representative and followed longitudinally from early adolescence into adulthood with 4 in-home interviews during the period 1994-2009. Add Health has collected rich longitudinal social, behavioral, environmental, and biological data, as well as buccal cell DNA from all sample members, including siblings pairs. Add Health has an enlightened dissemination policy and to date has released phenotype and genotype data to more than 10,000 researchers in the scientific community.

Carolina Digital Repository (University of North Carolina at Chapel Hill), 2009

This study aimed to examine perceptual factors associated with condom use, and the relationship b... more This study aimed to examine perceptual factors associated with condom use, and the relationship between condom use and the timing of sexual debut, among male secondary-school students in Nairobi, Kenya. Data are from the TeenWeb study, a school-based project that used the World Wide Web to assess the health needs of secondary-school students, and tested the web's utility as a teaching and research modality. Analyses are based on 214 sexually experienced males aged 14 to 20 years who completed web-based questionnaires about their sexual attitudes and behaviour. Results indicate that students did not see themselves as susceptible to HIV/AIDS and believed condom effectiveness in preventing HIV to be low. Consequently, only a marginal association was found between agreeing that buying condoms is embarrassing and condom use at first sexual intercourse. However, contrary to expectation, agreeing that condoms often break (almost half of participants) was associated with a higher likelihood of condom use at first sex. Each year of delay in sexual debut increased the likelihood of using a condom at first sex by 1.44 times. In turn, having used a condom at first sex increased the likelihood of using one at the most recent sex by 4.81 times, and elevated general condom use ("most or all the time") by 8.76 times. Interventions to increase awareness about the role of condoms in preventing HIV, delay sexual initiation, and teach proper condom use among secondary-school students in Nairobi are needed.

Journal of Epidemiology and Community Health, Sep 6, 2018

Journal of Research on Adolescence, Apr 9, 2010

A theoretical model of gender differences in depressive symptoms during adolescence was evaluated... more A theoretical model of gender differences in depressive symptoms during adolescence was evaluated using data from Waves I and II of the National Longitudinal Study of Adolescent Health. The theoretical model under examination was primarily informed by the gender-additive model of gender differences in depressive symptoms during adolescence proposed by . In the model, it was posited that BMI would be associated with perceiving oneself as overweight, which would then lead to a higher probability of dieting, which would be associated with greater depressive symptoms. Participants were 10,864 male and female adolescents. Gender did not moderate any of the model pathways, but mediation analysis indicated that gender differences in changes in depressive symptoms were mediated by perceived weight status and dieting. Findings suggest that one explanation for girls' higher depressive symptoms in adolescence relative to boys is girls' greater tendencies to perceive themselves as overweight and to diet. Depression affects women at a rate twice as high as that observed among men . Before adolescence, depressed males may actually outnumber their female peers, but at approximately age 13 or 14, depression becomes more prevalent among females than males . Studies using continuous, self-report measures of depressive symptoms have found that girls begin to evidence significantly higher mean levels of depressive symptoms relative to boys at the age of 13 or 14 . This pattern has been supported by meta-analysis . Efforts to explain gender differences in depression during adolescence typically have examined suspected risk factors for depression (e.g., rumination, communion, body dissatisfaction, stressful events) individually as mediators of gender differences in depression or have examined gender as a moderator of the relationship between the risk factor and depression . Conceptually, mediation of the relationship between two variables occurs when the effect of one variable on the other is exerted through an intervening variable . Mediation models of gender differences in depression therefore capture the extent to which the effect of gender on depression is transmitted through a given variable or mediator.

Inter-temporal choice represents one of the most fascinating topics in economics. Understanding i... more Inter-temporal choice represents one of the most fascinating topics in economics. Understanding its determinants can provide vital insight into decisions ranging from savings and financial investment to smoking, obesity and human capital accumulation. This article contributes to a growing literature that seeks to identify the determinants of inter-temporal choice. We explore the role of income shocks, age and gender on time discounting using evaluation data from the Government of Kenya's largest social protection programme, the Kenya Cash Transfer for Orphans and Vulnerable Children (CT-OVC). Study participants were randomised to treatment and control arms in 2007 and data on time discounting was collected on participants four years after programme inception. Our paper confirms that middle-aged groups are more patient than younger and older adults. In contrast to the empirical evidence, females are less patient than males and this situation is more evident during young and adult life. Males lose their patient during old age. Considering the impact of the programme, the average treatment effect of the programme on time discounting is negligible. However, it varies strongly with age of the recipient, with large and statistically significant effects among prime-age recipients and no effects on younger or older recipients. Moreover, these results are stronger for females than males, an important result given that over 60 per cent of recipients in target households are females.