Patterns of adolescent sexual behavior predicting young adult sexually transmitted infections: a latent class analysis approach

Latent classification model for censored longitudinal binary outcome

Latent classification model is a class of statistical methods for identifying unobserved class membership among the study samples using some observed data. In this study, we proposed a latent classification model that takes a censored longitudinal binary outcome variable and uses its changing pattern over time to predict individuals' latent class membership. Assuming the time-dependent outcome variables follow a continuous-time Markov chain, the proposed method has two primary goals: (1) estimate the distribution of the latent classes and predict individuals' class membership, and (2) estimate the class-specific transition rates and rate ratios. To assess the model's performance, we conducted a simulation study and verified that our algorithm produces accurate model estimates (ie, small bias) with reasonable confidence intervals (ie, achieving approximately 95% coverage probability). Furthermore, we compared our model to four other existing latent class models and demonstrated that our approach yields higher prediction accuracies for latent classes. We applied our proposed method to analyze the COVID-19 data in Houston, Texas, US collected between January first 2021 and December 31st 2021. Early reports on the COVID-19 pandemic showed that the severity of a SARS-CoV-2 infection tends to vary greatly by cases. We found that while demographic characteristics explain some of the differences in individuals' experience with COVID-19, some unaccounted-for latent variables were associated with the disease.

Definitions of Having Sex in Older Men and Women and Their Relationship with Sexual Well-Being

The goal of this study was to explore the sexual activities that older adults consider as having had sex and to examine correlates of the ways that older men and women define sex. A sample of 286 men and women aged 60 years and older who were involved in a romantic relationship were recruited online from Prolific and Facebook advertisements. Participants were presented a list of 19 different sexual activities and asked whether they would think they had sex if they engaged in each one of those activities. Results showed that penetrative sexual activities were found to be the most likely endorsed as having had sex, followed by genital non-penetrative activities, masturbation activities, and non-genital contact. Greater sexual frequency for a sexual activity was associated with endorsing that same activity as having had sex. A cluster analysis revealed five different groups of individuals based on the activities that they considered as having had sex. Only small differences in sexual wellbeing were found among these groups of individuals. The way older men and women define sex is complex and shows great variability. Our results have important implications for the operationalization and assessment of sexual activity. Other implications for healthcare and future research are discussed.

Exploring the relationship between mothers' competence and comfort in sexual and reproductive health discourse with adolescent girls and its related factors

OBJECTIVES

The mothers-adolescent discussion regarding sexual and reproductive health (SHR) issues plays an important role in preventing negative outcome associated with sexual risk behaviors. The present study aimed to explore the relationship between mothers' competence and comfort in SHR discourse with adolescent girls and its related factors.

METHODS

A cross-sectional study was conducted involving 160 mothers from July to September 2020. Data were collected through questionnaires covering demographic characteristics, Mother's Comfort in Sexual Discourse (MCSD), Mother's Interest in Sexual Discourse (MISD), and Parenting Sense of Competence (PSOC). The collected data were analyzed using simple and multiple linear regression models.

RESULTS

The mean scores for MCSD, MISD, and PSOC were 45.49±16.15 (13-78), 7.9±4.2 (0-13), and 64.07±9.44 (45-94), respectively. The primary topics of mother-adolescent discourse on SRH were menstruation (5.61±0.98) and the delivery process (4.55±1.57). The mean age for "sex talks" and age-appropriate "sex talks" with daughters was 11.76±1.85 (range: 6-15) and 17.05±1.86 (range: 14-23) years, respectively. Significant associations were found between MCSD and MISD (β=0.482, p<0.0001), PSOC (β=0.223, p<0.005), self-efficacy (β=0.202, p<0.011), mother's job (β=0.185, p<0.019), mother's education (β=0.173, p<0.029), and father's age (β=0.161, p<0.042). After adjusting for other variables, major influencing factors on MCSD included MISD (β=0.487, p<0.0001), self-efficacy (β=0.143, p<0.039), satisfaction (β=0.169, p<0.015), daughter number (β=-0.235, p<0.014), son number (β=-0.219, p<0.024), birth rank (β=0.263, p<0.008), and residency (β=0.172, p<0.014).

CONCLUSIONS

MISD, PSOC, and certain demographic characteristics emerge as significant factors influencing MCSD in mother-daughter sexual discourse. As such, it is imperative to consider these determinants when devising strategies to maintain and enhance the sexual health of teenage girls.

U.S. College Students' Sexual Risk Behaviors Before and During the Early COVID-19 Pandemic

The present study describes changes in young adults' sexual behaviors during the early COVID-19 pandemic. Latent class growth analyses (LCGAs) conducted with four waves of data collected between July 2019 to May 2020 in N = 775 college students (Mage = 18.61, SD = 0.33; 50.3% female, 90.2% White) revealed the presence of high- and low-risk classes in separate models for oral, vaginal, and anal sexual risk taking. As anticipated, vaginal and oral risk taking declined in spring 2020. Membership in high-risk trajectories was attributable to high COVID-19-related financial problems, early sexual debut, low self-control, and being in a romantic relationship. Other COVID-19 factors and demographic control variables were not linked to trajectory membership. Thus, while many young adults' sexual risk taking changed during the early pandemic, their perceptions of and experiences with COVID-19 were not predictive of sexual risk trajectory membership.

Sexual health variation among gang-involved youth in Washington state: Social ecological implications for research and practice

INTRODUCTION

Gang-involved youth experience greater disparities in sexual health compared to non-gang-involved youth. Yet, little is known about how and why sexual behaviors vary within the youth gang population. Developing relevant and effective service approaches requires an understanding of this variation and the environmental factors that influence patterns of sexual health risk.

METHODOLOGY AND RESULTS

Using latent class analysis, we identified four sexual behavior classes within a school-based sample of gang-involved youth in Washington State (N = 2060): Non-Sexually Active (54%), Limited Partners with Condom Use (14%), Multiple Partner with Sexting (19%), and High Sexual Vulnerability (13%). These classes were distinguished by age at sexual debut, number of sexual partners, condom use, and sexting. Interpersonal and macrosocial factors differentiated the classes, including multiform violence exposures, limited social support, and socioeconomic instability. We also found differences according to sexual identity and substance use.

DISCUSSION

Findings highlight the need for service approaches that are responsive to both the individual needs of gang-involved youth and the factors that shape their living environments. We discuss the implications for research and practice, including the potential utility of a harm reduction framework to promote sexual health and reduce disparities in the youth gang population.

Socio-ecologic Correlates of HIV/AIDS-Related Sexual Risk Behavior of African American Emerging Adults

There is growing evidence showing that patterns of individual sexual risk behaviors are insufficient in explaining the disproportionate HIV/AIDS burden borne by African Americans. Instead, dynamic features of social, economic, political, and geographic contexts play a more determining role. However, not enough studies have examined the impact of multi-level factors including neighborhood-level influences on HIV/AIDS sexual risk among African American emerging adults using a socio-ecologic perspective. Anchored on the socio-ecologic framework, this study examines the collective role of relevant socio-ecologic determinants of sexual risk-taking among African American emerging adults. Results from both bivariate and multivariate analyses revealed that individual and neighborhood-level variables were significantly associated with sexual risk in our study population partially confirming the hypothesis of the study. Male gender, educational attainment, and neighborhood social disorder were the strongest predictors of sexual risk. Our findings contribute to the vast literature on sexual risk behavior patterns of young adults, and increasing evidence demonstrating the role of contextual factors as stronger predictors of sexual risk and HIV infection among at-risk youth. Our findings, however, underscore the need for further research on the pathways of HIV socio-behavioral vulnerability in this demographic group.

"I wish I actually had known what the heck sex was:" What adolescent sexual minority males knew and wish they knew prior to sexual debut with a male partner

Introduction

Understanding the sexual health needs of adolescent sexual minority males (ASMM) at the time of sexual debut will inform programs seeking to decrease sexual health inequities experienced by ASMM.

Methods

In 2020, sexually active, cisgender ASMM (n=102, age 14-17) in the United States completed the baseline assessment of an online sexual health intervention pilot trial. Participants responded to closed- and open-ended questions about their sexual debut with a male partner, including sexual behavior, skills and knowledge they knew and wish they knew at the time of their debut, and sources of said skills and knowledge.

Results

On average, participants were 14.5 years old (SD=1.4) at their debut. Participants reported knowing how to say no to sex (80%) and wishing they knew how to talk with partners about what they would (50%) and would not (52%) like to do sexually. Open-ended responses indicated that participants desired sexual communication skills at sexual debut. Personal research (67%) was the most common knowledge source prior to debut, and open-ended responses suggest that Google, pornography, and social media were the most frequently used websites and phone applications to find information about sex.

Conclusions

Results suggest sexual health programs for ASMM should occur prior to sexual debut, teach sexual communication skills, and teach media literacy skills to help youth deduce credible sexual health resources.

Policy Implications

Incorporating the sexual health needs and wants of ASMM into sexual health programs will likely improve acceptability and efficacy, and ultimately decrease sexual health inequities experienced by ASMM.

Sexual Behavior Patterns of Black Young Adults in Georgia: Results from a Latent Class Analysis

The state of Georgia ranks first in the rate of new diagnosis of HIV/AIDS, yet studies focused on understanding the drivers of this epidemic in the most at-risk groups outside the Atlanta Metropolitan Statistical Area (MSA) remain sparse. Among the many consequences of this is the inability to effectively design tailored intervention programs that appropriately address the reduction of HIV/AIDS and other STDS in the state. Reducing disparities in HIV/AIDS remains an important goal in the National HIV/AIDS Strategy. Given the disproportionate burden of the HIV/AIDS epidemic among Blacks in the state of Georgia, there is a significant need to focus research attention on the sexual behavior of young people that predisposes them to increased risk of HIV/AIDS infection. The current study used latent class analysis (LCA) to examine the sexual behavior patterns of Black young adults living in Georgia. LCA results revealed a two-class fit with distinct sexual behavior patterns. Gender and educational attainment emerged as significant predictors of class membership. Our findings contribute to the vast literature showing that sexual behavior patterns of Black young adults are not homogenous, and underscore the significance of socio-demographic and contextual factors in shaping sexual risk behavior.

Predicting Risky Sexual Behavior Among College Students Through Machine Learning Approaches: Cross-sectional Analysis of Individual Data From 1264 Universities in 31 Provinces in China

BACKGROUND

Risky sexual behavior (RSB), the most direct risk factor for sexually transmitted infections (STIs), is common among college students. Thus, identifying relevant risk factors and predicting RSB are important to intervene and prevent RSB among college students.

OBJECTIVE

We aim to establish a predictive model for RSB among college students to facilitate timely intervention and the prevention of RSB to help limit STI contraction.

METHODS

We included a total of 8794 heterosexual Chinese students who self-reported engaging in sexual intercourse from November 2019 to February 2020. We identified RSB among those students and attributed it to 4 dimensions: whether contraception was used, whether the contraceptive method was safe, whether students engaged in casual sex or sex with multiple partners, and integrated RSB (which combined the first 3 dimensions). Overall, 126 predictors were included in this study, including demographic characteristics, daily habits, physical and mental health, relationship status, sexual knowledge, sexual education, sexual attitude, and previous sexual experience. For each type of RSB, we compared 8 machine learning (ML) models: multiple logistic regression (MLR), naive Bayes (BYS), linear discriminant analysis (LDA), random forest (RF), gradient boosting machine (GBM), extreme gradient boosting (XGBoost), deep learning (DL), and the ensemble model. The optimal model for both RSB prediction and risk factor identification was selected based on a set of validation indicators. An MLR model was applied to investigate the association between RSB and identified risk factors through ML methods.

RESULTS

In total, 5328 (60.59%) students were found to have previously engaged in RSB. Among them, 3682 (41.87%) did not use contraception every time they had sexual intercourse, 3602 (40.96%) had previously used an ineffective or unsafe contraceptive method, and 1157 (13.16%) had engaged in casual sex or sex with multiple partners. XGBoost achieved the optimal predictive performance on all 4 types of RSB, with the area under the receiver operator characteristic curve (AUROC) reaching 0.78, 0.72, 0.94, and 0.80 for contraceptive use, safe contraceptive method use, engagement in casual sex or with multiple partners, and integrated RSB, respectively. By ensuring the stability of various validation indicators, the 12 most predictive variables were then selected using XGBoost, including the participants' relationship status, sexual knowledge, sexual attitude, and previous sexual experience. Through MLR, RSB was found to be significantly associated with less sexual knowledge, more liberal sexual attitudes, single relationship status, and increased sexual experience.

CONCLUSIONS

RSB is prevalent among college students. The XGBoost model is an effective approach to predict RSB and identify corresponding risk factors. This study presented an opportunity to promote sexual and reproductive health through ML models, which can help targeted interventions aimed at different subgroups and the precise surveillance and prevention of RSB among college students through risk probability prediction.

Does Context and Adversity Shape Sexual Behavior in Youth? Findings from Two Representative Samples of Puerto Rican Youth

Sexual risk behaviors often co-occur. Understanding the heterogeneity in patterns of sexual behavior among youth and how context of majority and minoritized status may be related to these behaviors can inform targeted STIs/HIV interventions. Data are from the Boricua Youth Study, a longitudinal study of two probability samples of Puerto Rican youth recruited in the South Bronx (SBx) and the metropolitan area in Puerto Rico (PR). We identified patterns of sexual behaviors among young adults (ages 15-24) with sexual experience (N = 1,203) using latent class analysis. Analyses examined context differences and the prospective relationship between adverse childhood experiences (ACEs) (childhood maltreatment/violence, family/parental dysfunction) and patterns of sexual behaviors (age at first sex, number of sex partners, sex with a high-risk partner, condom use, sex while intoxicated, oral sex, anal sex). We identified five classes of sexual behaviors: (1) currently inactive (16.51%); (2) single partner, low activity (13.49%); (3) single partner, inconsistent condom use (32.19%); (4) single partner, sex without a condom (27.65%); and (5) multirisk (10.16%). Young adults from the SBx (minoritized context), those who identified as male, and those with higher child maltreatment/violence ACEs were more likely to be in the multi-risk class relative to the single partner, inconsistent condom use class. Those from the SBx were also more likely to be in the single partner, sex without condom class, relative to the single partner, inconsistent condom use class. Differences in young adults' patterns of sexual behaviors between the two contexts, one representing the minoritized context (SBx) contrasted to the majority context (PR), were not explained by ACEs. Findings highlight the heterogeneity in the patterns of sexual behaviors among Puerto Rican young adults as well as how such patterns vary based on sociocultural contexts. Exposure to child maltreatment/violence ACEs was related to the riskier patterns; however, they did not explain why riskier patterns of sexual behaviors were found in the SBx compared to PR. Results underscore the need for tailored interventions and more in-depth examination of differences across contexts.

Adolescent Relationship Abuse, Gender Equitable Attitudes, Condom and Contraception Use Self-Efficacy Among Adolescent Girls

Introduction: Experiencing adolescent relationship abuse (ARA) negatively impacts sexual health and influences risk behaviors of adolescent girls. ARA may be associated with more inequitable gender attitudes among girls, a potentially modifiable factor in violence prevention. This study examines the association among gender equitable attitudes, experiences of ARA, and sexual behaviors among girls participating in Sisterhood 2.0, a community-based violence prevention program implemented in low resource neighborhoods. Methods: Data were from baseline surveys collected for Sisterhood 2.0 implemented in Pittsburgh, PA. Participant demographics, gender equitable attitudes, self-efficacy to use condoms with partners, and self-efficacy to select appropriate contraception were assessed. A latent class analysis (LCA) estimated probability of responses to nine indicators, including sexual behavior self-efficacy and violence. Multigroup LCA by grade (9-12) was also estimated and analyses were performed with SAS V9.4. Results: Female-identified adolescents ages 13-19 (n = 246) were primarily Black (75%) and evenly distributed across grade in school. Sixty-five percent reported emotional relationship abuse and 31% reported physical abuse within the previous nine months. A three-class solution was best fitting for the LCA. Experiences of violence were related to less equitable gender attitudes, being sexually active, and lower condom and contraception self-efficacy. Younger participants who were sexual minorities with less educated heads of household had more experiences with ARA and less equitable gender attitudes. Discussion: Gender equitable attitudes were lower in adolescent girls with greater experiences of ARA and worse condom and contraception self-efficacy. Integrating discussions about healthy sexual relationships and gender equity may be salient factors in violence prevention.

Sexual Behavior and Health From Adolescence to Adulthood: Illustrative Examples of 25 Years of Research From Add Health

Due to its long-term longitudinal design, the National Longitudinal Study of Adolescent to Adult Health (Add Health) has provided numerous valuable insights into adolescent and young adult sexual behavior. Framed by a conceptual model of sexual behavior and health, I review research using Add Health data to study sexual behavior and health. In this paper, I review research examining both predictors (e.g., neighborhood, family, genetic, individual) and health outcomes (e.g., sexually transmitted infections, mental health) of sexual behavior in adolescents and young adults. Where possible, I focus on long-term longitudinal studies that make use of the unique strengths of the Add Health data. Existing Add Health research has provided considerable information about both the predictors and health consequences of adolescent and young adult sexual behavior. Factors ranging from neighborhoods to genetics predict whether adolescent and young adults engage in sexual behaviors. Findings on long-term outcomes of adolescent sexual behavior suggest that early sexual behavior predicts higher rates of sexually transmitted infections and pregnancy in young adulthood, but not long-term changes to mental health. Unique contributions of Add Health include the ability to examine multidimensional bio-ecological predictors of sexual behavior and to examine long-term effects of sexual behavior and how sexual behaviors and their correlates change across adolescence into adulthood. Future work can leverage these strengths, and in particular the long-term longitudinal nature of the data, to uncover new insights about the developmental course of sexual behavior and health.

Is Regulatory Focus Related to Condom Use, STI/HIV Testing, and Sexual Satisfaction?

Regulatory focus theory contends that when making decisions people are either more inclined to focus on avoiding negative consequences (more prevention-focused) or achieving pleasurable outcomes (more promotion-focused). Some research suggests that regulatory focus is related to health behaviors, although this has not been thoroughly investigated in the sexual health domain. The purpose of this study was to examine the relationship between regulatory focus (prevention, promotion) and sexual health. In an online survey of 409 youth from the U.S. (ages = 18-25; M_age = 23.5; 57.2% women; 74.1% White, 13.4% Asian, 10.5% Black, 9.8% Hispanic), we examined the relationship between regulatory focus and three sexual health outcomes: condom use, STI/HIV testing, and sexual satisfaction. Of youth in our sample, 31.8% had a dominant prevention-focus, while 54.8% had a dominant promotion-focus. Compared to youth who were more promotion-focused, more prevention-focused youth used condoms more frequently but reported less sexual satisfaction. No differences were found in rates of STI/HIV testing. This study lays the groundwork to investigate the dynamic role that regulatory focus may play in contributing to youths' sexual health. More experimental and longitudinal studies are needed to confirm the causal nature of the association between regulatory focus and sexual health.

Patterns of sexual behaviour associated with repeated chlamydia testing and infection in men and women: a latent class analysis

BACKGROUND

Adolescents and young adults are at higher risk of acquiring Chlamydia trachomatis infection (chlamydia), so testing is promoted in these populations. Studies have shown that re-testing for chlamydia is common amongst them. We investigated how sexual risk behaviour profiles are associated with repeated testing for chlamydia.

METHODS

We used baseline data from a cohort of 2814 individuals recruited at an urban STI -clinic. We applied latent class (LC) analysis using 9 manifest variables on sexual behaviour and substance use self-reported by the study participants. We fitted ordered logistic regression to investigate the association of LC membership with the outcomes repeated testing during the past 12 months and lifetime repeated testing for chlamydia. Models were fit separately for men and women.

RESULTS

We identified four LCs for men and three LCs for women with increasing gradient of risky sexual behaviour. The two classes with the highest risk among men were associated with lifetime repeated testing for chlamydia: adjOR = 2.26 (95%CI: 1.50-3.40) and adjOR = 3.03 (95%CI: 1.93-4.74) as compared with the class with lowest risk. In women, the class with the highest risk was associated with increased odds of repeated lifetime testing (adjOR =1.85 (95%CI: 1.24-2.76)) and repeated testing during past 12 months (adjOR = 1.72 (95%CI: 1.16-2.54)). An association with chlamydia positive test at the time of the study and during the participant's lifetime was only found in the male highest risk classes.

CONCLUSION

Prevention messages with regard to testing for chlamydia after unprotected sexual contact with new/casual partners seem to reach individuals in highest risk behaviour classes who are more likely to test repeatedly. Further prevention efforts should involve potentially more tailored sex-specific interventions taking into consideration risk behaviour patterns.

More than the sum of their parts: A dyad-centered approach to understanding adolescent sexual behavior

BACKGROUND

Research has documented multiple levels of influences on adolescent sexual behavior, but has generally focused less on the relational nature of this behavior. Studies with dyadic data have provided important findings on relationship process, including the role of gender in different-sex dyads. However, both of these bodies of literature typically utilize a variable-centered approach, which examines average influences of particular variables on sexual behavior. This study expands upon this research by presenting a dyad-centered approach to adolescent sexual behavior that can identify types of couples based on patterns of multidimensional risk and protective factors.

METHODS

I demonstrate the dyad-centered approach using data from different-sex dyads in the National Longitudinal Study of Adolescent to Adult Health to uncover profiles marked by individual, parent, peer, and religion predictors for both male and female partners.

RESULTS

Analyses uncovered five classes of dyadic influences, four of which were marked by relative similarity between partners and one marked by lesser approval of sex for women compared to men. Dyads marked by both partners intending to have sex and being in a context that is more approving of sex were more likely to engage in sexual intercourse.

CONCLUSIONS

Findings demonstrate the heterogeneity of influences and intentions to have sex among adolescent couples, and identify profiles of dyads who are more likely to engage in sexual intercourse. This approach can explicate dyadic processes involved in sexual behavior and the types of couples that exist in a population, leading to more tailored and efficacious interventions.

A Latent Class Analysis of Sexual Behavior and Associations with Sex Education, Smoking, Drinking, and Pornography Use Among Chinese Youth

The incidence of sexually transmitted diseases has alarmingly increased among Chinese youth in the past decade, and newly diagnosed cases of AIDS have almost doubled between 2010 and 2015. However, little is known about classes of sexual behavior among Chinese youth and associations with their other health behavior or experience of sex education. This study aimed to first identify classes of sexual behavior using latent class analysis and then to examine their associations with sex education, smoking, alcohol drinking, and pornography use. Data were from 13,865 unmarried youth aged 18-24 from the 2009 National Youth Reproductive Health Survey. Six indicators were used: timing of the first sexual intercourse, the number of past-year sexual partners, sex outside of a relationship, incidence of pregnancy, and contraceptive use at the latest and the first sexual intercourse. Four classes were identified: no sex (Class 1, 69%), safer sex (Class 2, 13%), early risk (Class 3, 13%), and multiple risk (Class 4, 5%). Smoking, drinking, and regular pornography use were associated with increased odds of being in the multiple risk class relative to the safer sex class. Sex education, smoking, and pornography use were associated with decreased odds of being in the no sex class relative to the safer sex class. The findings revealed qualitatively different classes of sexual behavior among Chinese youth and important roles of sex education, substance use, and pornography use. Reproductive health service providers can offer individually tailored services to serve youth with different profiles and needs.

The Intersection of Intimate Partner Violence Perpetration and Sexual Risk Behavior Among Young Men in Tanzania: A Latent Class Analysis of Patterns and Outcomes

Few studies of intimate partner violence (IPV) perpetration and sexual risk behavior among men have examined how multiple dimensions of these behaviors intersect in ways that may uniquely elevate health risks. The current study used latent class analysis to: (1) identify distinct patterns of IPV and sexual risk behavior in a sample of Tanzanian men (n = 985) and (2) examine associations between identified patterns and health outcomes. Four classes were identified: normative (64% of the sample), IPV only (14%), sexual risk only (13%), and comorbid IPV/sexual risk (5%). Compared to men in the normative subgroup, men in the comorbid group had significantly higher odds of STI infection, higher perceived HIV risk, and greater odds of substance use. Findings provide evidence that engaging in IPV and multiple sexual partnerships (i.e., a comorbid pattern) denotes elevated health risks across a range of indicators, suggesting the importance of targeted treatment and prevention efforts for men in this subgroup.

Latent Profiles of Internal and External Consent During a Recent Sexual Encounter

Understanding how individuals conceptualize and communicate sexual consent is critical to sexual health and has important implications for the prevention of sexual assault. This study used a data-driven (vs. a theoretical) approach to understand how students' internal feelings of willingness (i.e., internal consent) and behavioral communication of consent (i.e., external consent) cluster together within sexual encounters. Using data from 610 college students (72% female) who reported on their most recent sexual encounter, latent profile analysis revealed five distinct consent profiles. Most students reported willing encounters that involved the use of several external consent cues (68.9%), a small group reported low levels of both internal and external consent (3.8%), and three groups (27.3% altogether) reported encounters with complex patterns of internal and external consent. Demographic and encounter-level differences were observed across profiles. Programming that trains students to attend to their own internal desires in addition to external consent behaviors could improve emotional health and shift social norms about sexual communication.

Relationship between Perceived Peer and Adolescents' Sexual Behaviors: The Moderating Role of Gender

In Malaysia, sexual health risks such as unprotected sex, teenage pregnancies, abandoned babies, abortion, and sexually transmitted diseases are on the rise because adolescents are increasingly engaging in such sexual behaviors. The present study aimed to investigate the relationship between perceived peer sexual behaviors and sexual behaviors among adolescents as well as to examine the interacting role of gender in such a relationship. This cross-sectional study recruited a sample of 338 school-going adolescents (M_age = 16.7; SD_age = 1.53) using the purposive sampling method. Participants were required to complete questionnaires consisting of the modified Human Sexuality Questionnaire-Orgasmic Experience Scale and the Peer Norms Scale. Results indicated that adolescents who perceived their peers to be actively engaging in sexual behaviors were more prone to being sexually active themselves. The results also showed gender as a significant moderator in the relationship between adolescents' perceived peers' sexual behaviors and sexual behaviors. Besides, the impact of perceived peer sexual behaviors on sexual behaviors was found to be stronger in male than female adolescents. Overall, the findings from this study hinted at the importance of peers and gender differences during the planning and implementation of sexual and health education.

Adolescent Sexual Behavior Patterns, Mental Health, and Early Life Adversities in a British Birth Cohort

This study tested adolescent sexual behavior patterns at age 14, their association with mental health at age 17 (psychological well-being, substance use, and self-harm attempts), and the influence of early life adversities upon this association. A British birth cohort (5,593 boys and 5,724 girls from the Millennium Cohort Study) was used. Latent class analysis suggested five subgroups of adolescent sexual behaviors: a "no sexual behavior" (50.74%), a "kisser" (39.92%), a "touching under clothes" (4.71%), a "genital touching" (2.64%), and an "all sexual activities" class (1.99%). Adolescents from the "kisser," "touching under clothes," "genital touching," and "all sexual activities" classes reported significantly more substance use and self-harm attempts compared to adolescents from the "no sexual behavior" group. The associations became weaker after controlling for early life adversities (reducing around 4.38% to 37.35% for boys, and 9.29% to 52.56% for girls), and reduced to a smaller degree after further controlling for mental health variables at 14. The associations between sexual behaviors and psychological well-being became non-significant after controlling for early life adversities. Adolescents who have engaged in low-intensity sexual activities at early age may have poorer reported mental health, a pattern that is stronger for girls and early life adversity may partially explain this association.

Typologies of Sexual Health Vulnerability Predicting STI Preventive Behaviors Among Latinx Adults in the U.S.: A Latent Class Analysis Approach

Vulnerability to poor sexual health among U.S. Latinx populations is poorly understood, despite high STI rates. We examined how vulnerability typologies differ in their STI preventive behaviors. Using data from the 2016 National Health Interview Survey, we performed latent class analysis to test the association between sexual health vulnerability and HIV testing, hepatitis testing or vaccination, and HPV vaccination from a subsample of Latinx adults. Three classes emerged: Under-Employed Females with Health Care Access, Slightly Under-Employed Females with Some Health Care Access, and Employed Males without Health Care Access. Slightly Under-Employed Females with Some Health Care Access were associated with lack of HIV testing, hepatitis B and C testing, and HPV vaccination. Employed Males without Health Care Access were associated with lack of HIV testing and HPV vaccination. Sexual health vulnerability may be associated with certain STI preventive behaviors, which can inform and refine sexual health promotion programming.

Adolescent Sexual Behavior Patterns in a British Birth Cohort: A Latent Class Analysis

This study examined adolescent sexual behaviors patterns, and the consistency between sexual behavior and sexual orientation, in a prospective birth cohort. We used data on 5150 young people from the Avon Longitudinal Study of Parents and Children. Sexual orientation was assessed using a 5-point scale of sexual attraction at 15.5 years. Fourteen sexual activities were assessed using the Adolescent Sexual Activities Index at 13.5 and 15.5 years. Latent class analysis suggested four subgroups of adolescent sexual behaviors at 13.5: a "high-intensity sexual behaviors exclusively with other-sex, no same-sex intimacy" group (3.87%); a "moderate-intensity sexual behaviors exclusively with other-sex, no same-sex intimacy" group (16.57%); a "low-intensity sexual behaviors exclusively with other-sex, no same-sex intimacy" group (34.21%); and a "no sexual behavior" group (45.35%). There were five subgroups at 15.5 where four of them (23.42%, 18.37%, 28.12%, and 24.52%, respectively) were interpreted the same as at 13.5 years and a new "high-intensity sexual behaviors, some same-sex intimacy" subgroup (5.57%). Latent transition analysis showed approximately half the adolescents moved toward greater engagement in higher intensity sexual activities with other-sex at 15.5. Boys and girls who were in groups without same-sex intimacy were predominantly attracted to the other-sex, whereas there were moderate consistencies between same-sex intimacy and same-sex attraction for boys and low consistency for girls. Findings suggest that it may be important to include low-intensity sexual behaviors when assigning adolescents to sexual orientation groupings (via sexual behaviors) in order to reduce selection biases and increase statistical power via the increase in sample size.

Parents Matter: Associations Between Parent Connectedness and Sexual Health Indicators Among Transgender and Gender-Diverse Adolescents

CONTEXT

Transgender and gender-diverse youth experience significant health disparities across numerous domains of health, including sexual health. Among general populations, parent connectedness has been strongly associated with youth sexual health.

METHODS

The relationships between parent connectedness and sexual health indicators were investigated among 2,168 transgender and gender-diverse youth who participated in the 2016 Minnesota Student Survey, a statewide population-based survey of ninth- and 11th-grade students. Multivariate logistic regression models, stratified by sex assigned at birth, tested associations between parent connectedness-youth's perceptions of parent caring and parent-youth communication-and eight sexual health indicators: ever having had sex, having multiple sexual partners in the past year, pregnancy involvement, substance use at last sex, partner communication about STI prevention, partner communication about pregnancy prevention, condom use at last sex and pregnancy prevention methods at last sex.

RESULTS

The level of parent connectedness was inversely associated with ever having had sex, regardless of sex assigned at birth (odds ratios, 0.6-0.8). Although level of connectedness was inversely associated with having multiple sexual partners in the past year and pregnancy involvement among transgender and gender-diverse youth assigned male at birth (0.6-0.7), these relationships were nonsignificant among transgender and gender-diverse youth assigned female at birth. Further differences in associations between parent connectedness and four sexual risk-reduction behaviors were found between youth assigned male at birth and those assigned female.

CONCLUSIONS

As with other populations, parent connectedness promotes sexual health among transgender and gender-diverse youth and may provide a point of intervention.

Trajectory Modelling Techniques Useful to Epidemiological Research: A Comparative Narrative Review of Approaches

Trajectory modelling techniques have been developed to determine subgroups within a given population and are increasingly used to better understand intra- and inter-individual variability in health outcome patterns over time. The objectives of this narrative review are to explore various trajectory modelling approaches useful to epidemiological research and give an overview of their applications and differences. Guidance for reporting on the results of trajectory modelling is also covered. Trajectory modelling techniques reviewed include latent class modelling approaches, ie, growth mixture modelling (GMM), group-based trajectory modelling (GBTM), latent class analysis (LCA), and latent transition analysis (LTA). A parallel is drawn to other individual-centered statistical approaches such as cluster analysis (CA) and sequence analysis (SA). Depending on the research question and type of data, a number of approaches can be used for trajectory modelling of health outcomes measured in longitudinal studies. However, the various terms to designate latent class modelling approaches (GMM, GBTM, LTA, LCA) are used inconsistently and often interchangeably in the available scientific literature. Improved consistency in the terminology and reporting guidelines have the potential to increase researchers' efficiency when it comes to choosing the most appropriate technique that best suits their research questions.

Serious and persistent suicidality among European sexual minority youth

BACKGROUND

Suicide is a leading cause of death among adolescents and more knowledge from high risk groups is needed in order to develop effective preventive strategies. The aim of this study was to evaluate the association between sexual minority status and suicidality in a multinational sample of European school pupils.

METHODS

A self-report questionnaire was delivered to 2046 adolescents (mean age 15.34±1.01; 56.3% females) recruited from 27 randomly selected schools in 6 European countries. Suicidal ideation, measured with the Paykel Suicide Scale (PSS), and lifetime suicide attempts were compared between heterosexual and sexual minority (i.e. those with a non-heterosexual orientation) youth. Poisson regression analyses studied the longitudinal association between sexual minority status and the rate of serious suicidal ideation, measured at three time-points during a 4-month period. Several variables, including alcohol and illegal drugs use, bullying, family interaction, school-related stress, economic status, and religiosity, were included in multivariable analysis. Sex-stratified analyses evaluated the association respectively among females and males.

RESULTS

Of 1958 pupils included in analysis (mean age 15.35±1.00; females 56.8%), 214 (10.9%) were categorized as sexual minority youth (SMY). When compared to heterosexual youth (HSY), SMY were significantly more exposed to substance abuse, bullying, school-related stress, and lower economic status. SMY pupils had significantly higher suicidal ideation scores (p<0.001; r 0.145) as well as higher prevalence of serious suicidal ideation (odds ratio [OR] 2.64, 95% confidence interval [CI] 1.83-3.79) and previous suicide attempts (OR 2.72, 95%CI 1.77-4.18), compared to their HSY peers. The rate of serious suicidal ideation reports during the study was significantly higher among SMY compared to HSY (rate ratio [RR] 2.55, 95%CI 1.90-3.43). A significant difference was found even when controlling for the pupils' country as well as after adjustment for alcohol and illegal drugs use, bullying, family interaction, school-related stress, economic status, and religiosity (adjusted RR 1.73, 95%CI 1.23-2.48). Stratified analyses showed significant associations between SMY status and persistent serious suicidal ideation for both sexes, with a notably strong association among male pupils (females aRR 1.51, 95%CI 1.01-2.24; males aRR 3.84, 95%CI 1.94-7.59).

CONCLUSIONS

European sexual minority youth are a high-risk group for suicidality, independently from objective factors such as victimization or substance abuse. There is a need to develop primary and secondary preventive measures for sexual minority youth, including the management of context vulnerabilities and related distal stressors, before the establishment of proximal stressors. Context-targeting interventions may effectively focus on social and economic factors, as well as on the potentially different risk profile of female and male sexual minority youth.

Illicit drug use and sexually transmitted infections among young adults in the US: evidence from a nationally representative survey

Young people aged 15-24 years account for half of all new sexually transmitted infections (STIs) in the United States. The aim of this study was to examine the cross-sectional associations of factors linked to STIs among US young adults (18-25 years). This study used the 2015-2018 pooled National Survey on Drug Use and Health data on 55,690 young adults. Almost 3.4% of the respondents reported having an STI in the past year. Among the participants, 38.4% used illicit drugs and 3.7% reported a history of delinquency in the past year. In the survey-weighted logistic regression model, odds for contracting STIs in the preceding year was higher among adults aged 22-25 versus 18-21 years (OR:1.26, 95%CI:1.12-1.42); male versus female (OR:2.44, 95%CI:2.11-2.82); non-Hispanic African American versus non-Hispanic White (OR:1.77, 95%CI:1.55-2.02); widowed/separated/divorced (OR:1.93, 95%CI:1.36-2.75) and never married (OR:1.29, 95%CI:1.07-1.55) versus married; full-time/part-time employed (aOR:1.17, 95% CI:1.04-1.31) compared to unemployed/other; history of delinquency (OR:2.31, 95%CI:1.89-2.83); and use of illicit drugs in the last year (OR:3.10, 95%CI:2.77-3.47). High incidence of illicit drug use by the young adults and its strong association with STI incidence in recent years warrant special attention. Tailored preventive measures should be focused on key predictors.

Associations Among Behavioral Risk, Sociodemographic Identifiers, and Sexually Transmitted Infections in Male and Female Army Enlisted Personnel

INTRODUCTION

Rates of sexually transmitted infections (STIs) are higher among U.S. military personnel than their civilian counterparts. Yet there is a paucity of military-specific research that has utilized theoretical frameworks to describe the relative influence of the multiple and interrelated risk factors associated with STIs in this population of young, healthy men and women. The aim of this study was to examine the relative influence of Information, Motivation, and Behavioral Skills Model (IMB) factors known to be associated with condom use and STI diagnosis, as well as examine gender differences among a cohort of young, active duty enlistees who are in the very early stages of their military careers.

MATERIALS AND METHODS

Data were collected in 2011 to 2013 through self-administered questionnaires and laboratory-confirmed tests of STIs. Logistic regression analyses were used to assess IMB constructs, behavioral risk variables, and sociodemographic factors associated with STI diagnosis and condom use separately among female and male military personnel.

RESULTS

STIs among males were significantly associated with nonwhite race, lower STI behavioral intentions and STI behavioral skills, and engaging in sex after drinking alcohol. Further, males who reported more positive attitudes toward using condoms, higher confidence in preventing drinking, higher alcohol prevention norms among peers, a lower frequency of drinking alcohol before engaging in sexual intercourse, more sexual partners, and higher STI behavioral intentions were significantly more likely to report using condoms consistently during sexual encounters. Among female participants, a history of STIs was significantly associated with higher numbers of reported sexual partners and greater alcohol prevention efficacy while lifetime consistent condom use was significantly associated only with stronger intentions to avoid behaviors that might result in STI acquisition.

CONCLUSION

Our findings support the need for development of STI prevention strategies that include education and skills-building approaches to reduce alcohol misuse among enlisted military personnel, and especially male personnel. Such programs should include factors that uniquely influence the experiences of males and females in the military context.

Clusters of HIV Risk and Protective Sexual Behaviors in Agincourt, Rural South Africa: Findings from the Ha Nakekela Population-Based Study of Ages 15 and Older

Understanding how sexual behaviors cluster in distinct population subgroups along the life course is critical for effective targeting and tailoring of HIV prevention messaging and intervention activities. We examined interrelatedness of sexual behaviors and variation between men and women across a wide age range in a rural South African setting with a high HIV burden. Data come from the Ha Nakekela population-based survey of people aged 15-85-plus drawn from the Agincourt Health and Socio-Demographic Surveillance System. We used latent class analysis of six sexual behavior indicators to identify distinct subgroup sexual behavior clusters. We then examined associations between class membership and sociodemographic and other behavioral risk factors and assessed the accuracy of a reduced set of sexual behavior indicators to classify individuals into latent classes. We identified three sexual behavior classes: (1) single with consistent protective behaviors; (2) risky behaviors; and (3) in union with lack of protective behaviors. Patterns of sexual behaviors varied by gender. Class membership was also associated with age, HIV status, nationality, and alcohol use. With only two sexual behavior indicators (union status and multiple sexual partners), individuals were accurately assigned to their most likely predicted class. There were distinct multidimensional sexual behavior clusters in population subgroups that varied by sex, age, and HIV status. In this population, only two brief questions were needed to classify individuals into risk classes. Replication in other situations is needed to confirm these findings.

Sexually Transmitted Infection Positivity Among Adolescents With or at High-Risk for Human Immunodeficiency Virus Infection in Los Angeles and New Orleans

BACKGROUND

Gay, bisexual, and transgender youth and homeless youth are at high risk for sexually transmitted infections (STIs). However, little recent data exist describing STI positivity by anatomical site among those groups. We determined the positivity of Chlamydia trachomatis (CT) infection, Neisseria gonorrhoeae (NG) infection, and syphilis antibody reactivity among lesbian, gay, bisexual, transgender, and homeless youth.

METHODS

We recruited 1,264 adolescents with high risk behavior aged 12 to 24 years from homeless shelters, lesbian, gay, bisexual, and transgender organizations, community health centers, and using social media and online dating apps in Los Angeles, California and New Orleans, Louisiana from May 2017 to February 2019. Participants received point-of-care pharyngeal, rectal, and urethral/vaginal CT and NG testing and syphilis antibody testing. We calculated STI positivity by anatomical site and compared positivity by participant subgroups based on human immunodeficiency virus (HIV) status, sex assigned at birth, and gender identity.

RESULTS

CT and NG positivity and syphilis antibody reactivity was higher among HIV-infected adolescent men who have sex with men (MSM) than HIV-uninfected adolescent MSM (40.2% vs. 19%, P < 0.05), particularly CT or NG rectal infection (28% vs. 12.3%, P < 0.05). Of participants with positive CT or NG infections, 65% had extragenital-only infections, 20% had both extragenital and urogenital infections, and 15% had urogenital-only infections.

CONCLUSIONS

Sexually transmitted infection positivity was high, particularly among transgender women and MSM. The high proportion of rectal and pharyngeal infections highlights the importance of both urogenital and extragenital STI screening. More accessible STI testing is necessary for high-risk adolescent populations.

Who is at risk? Gendered psychological correlates in Italian students’ sexual risk profiles

Recent research has shown that sexual risk behaviours are rising substantially among Italian youth, but this evidence is still undervalued in public discussion. Adopting a multidimensional perspective for sexual risk and addressing gender differences, the present study investigates if and how some individuals’ psychological characteristics—namely body satisfaction, self-esteem and body sensation-seeking—are associated with unsafe and risky sexual behaviours of Italian emerging adults. We exploited the survey SELFY—Sexual and Emotional LiFe of Youths—conducted in 2017 in Italy. Several key points may be highlighted from our study. First, we identify two clusters characterized by high sexual risk-taking behaviours, which include one third of our sample, a non-negligible proportion. Second, we prove that women are generally less inclined to adopt risk-taking behaviours in sexual life. Third, our findings show that body satisfaction, self-esteem and sensation seeking are differently linked to sexual risk taking among women and men. Body satisfaction is associated with a higher probability of adopting risky and promiscuous sexual behaviours among men, while the relationship is not significant among women. Sensation seeking shows a certain relevance in defining sexual risk profiles, especially for men. Overall, our research suggests that body image and self-worth could be relevant areas of intervention for sexual health programs targeting emerging Italian adults. Notably, communication and education strategies on these issues should be differentiated for women and men.

Creating HIV risk profiles for men in South Africa: a latent class approach using cross-sectional survey data

INTRODUCTION

Engaging at-risk men in HIV prevention programs and services is a current priority, yet there are few effective ways to identify which men are at highest risk or how to best reach them. In this study we generated multi-factor profiles of HIV acquisition/transmission risk for men in Durban, South Africa, to help inform targeted programming and service delivery.

METHODS

Data come from surveys with 947 men ages 20 to 40 conducted in two informal settlements from May to September 2017. Using latent class analysis (LCA), which detects a small set of underlying groups based on multiple dimensions, we identified classes based on nine HIV risk factors and socio-demographic characteristics. We then compared HIV service use between the classes.

RESULTS

We identified four latent classes, with good model fit statistics. The older high-risk class (20% of the sample; mean age 36) were more likely married/cohabiting and employed, with multiple sexual partners, substantial age-disparity with partners (eight years younger on-average), transactional relationships (including more resource-intensive forms like paying for partner's rent), and hazardous drinking. The younger high-risk class (24%; mean age 27) were likely unmarried and employed, with the highest probability of multiple partners in the last year (including 42% with 5+ partners), transactional relationships (less resource-intensive, e.g., clothes/transportation), hazardous drinking, and inequitable gender views. The younger moderate-risk class (36%; mean age 23) were most likely unmarried, unemployed technical college/university students/graduates. They had a relatively high probability of multiple partners and transactional relationships (less resource-intensive), and moderate hazardous drinking. Finally, the older low-risk class (20%; mean age 29) were more likely married/cohabiting, employed, and highly gender-equitable, with few partners and limited transactional relationships. Circumcision (status) was higher among the younger moderate-risk class than either high-risk class (p < 0.001). HIV testing and treatment literacy score were suboptimal and did not differ across classes.

CONCLUSIONS

Distinct HIV risk profiles among men were identified. Interventions should focus on reaching the highest-risk profiles who, despite their elevated risk, were less or no more likely than the lower-risk to use HIV services. By enabling a more synergistic understanding of subgroups, LCA has potential to enable more strategic, data-driven programming and evaluation.

The Effects of Trauma, Violence, and Stress on Sexual Health Outcomes Among Female Clinic Clients in a Small Northeastern U.S. Urban Center

Background: Threats to sexual health can emerge across one's life span and are influenced by individual and interpersonal experiences, as well as certain environmental exposures. Although previous research has recognized the importance of ecological frameworks to understand the complexity of health and behaviors in marginalized communities, there continues to be a dearth of research that truly utilizes this perspective to gain insight into the multifaceted factors that can concurrently influence threats to sexual health among women. Methods: A sample of 279 ethnoracially diverse women were recruited from a U.S. northeastern small urban center health clinic to participate in a parent study on trauma and immunity. A hierarchical block analysis was conducted to investigate associations between women's experiences of trauma, stress and violence (i.e., childhood trauma (CHT), intimate partner violence (IPV), neighborhood stressors), and sexual health outcomes and behaviors (i.e., lifetime sexually transmitted infection [STI] diagnosis, concurrent partnerships, and lifetime sex trading). Results: In the full hierarchical model, IPV and life stress trauma were associated with lifetime sex trading and partner concurrency. Also in the full model, sexual CHT was associated with lifetime STI acquisition and partner concurrency, while emotional CHT was associated with lifetime sex trading. Lastly, as neighborhood disorder increased, so did the number of lifetime sex trading partners. Conclusion: Sexual health assessments in clinical and community settings require a holistic, comprehensive, and meaningful approach to inform person-centered health promotion intervention. Prevention and treatment interventions require a focus on parents and families, and should assist adolescents and young adults to adopt therapies for healing from these experiences of trauma, violence, and stress. Interventions to enhance sexual health promotion must also include the following: advocacy for safe environments, social policy that addresses lifelong impacts of CHT, and fiscal policy that addresses economic vulnerability among women and threatens sexual health. Further recommendations are discussed.

Individual and Neighborhood Factors Associated With Sexual Behavior Classes in an Urban Longitudinal Sample

BACKGROUND

This study aimed to increase understanding of the clustering of sexual behaviors in an urban sample of emerging adults, and the individual and neighborhood factors associated with sexual behavior patterns to provide insight into reducing the disproportionate burden of poor sexual outcomes among urban African Americans.

METHODS

We draw on 2 cohorts of urban, predominantly African American youth first assessed at age 6 years and follow-up to emerging adulthood (mean age, 20 years; n = 1618). Latent class analyses by gender identified co-occurrence of sexual behavior.

RESULTS

We found 3 classes for both males and females: high-risk (13% of males, 15% of females), low-risk (54% of males, 56% of females) and no-risk (33% of males, 29% of females). Membership in the high-risk class was associated with school dropout, a substance use disorder diagnosis, having a criminal arrest, pregnancy, and sexually transmitted diseases for both males and females. High-risk females also had higher rates of depression. Low-risk males and females also had elevated risk of pregnancy and parenthood. Neighborhood factors distinguished the high- and no-risk classes for males and females, including the neighborhood environment scale, which assessed poverty, safety, drug activity, and crime/violence in the neighborhood. Neighborhood religiosity was inversely associated with membership in the high-risk class compared with the no-risk class for females only. Neighborhood racism distinguished those in the high-risk class compared with the no-risk class for males.

CONCLUSIONS

Future work should take into account the clustering of sexual risk behaviors. Specific neighborhood factors could be addressed to reduce sexual health disparities.

Predicting sexual behaviors from mid-adolescence to emerging adulthood: The roles of dating violence victimization and substance use

The purpose of the present study was to determine whether dating violence victimization (psychological, physical, and sexual) and substance use (alcohol and marijuana) predicted sexual behaviors that increase risk for poor outcomes from ages 15-19. Adolescents (N = 1042; 56% female) were recruited from high schools in Southeast Texas in 2010 and followed annually for six years. The mean age of the sample at baseline was 15.09 (SD = 0.79). Participants primarily identified as Hispanic (31.4%), White (29.4%), and Black/African American (27.9%). Participants completed measures of dating violence victimization, substance use, and sexual behaviors annually. We examined unique and interactive associations between substance use and dating violence victimization with sexual behaviors that increase risk for poor outcomes. Multilevel modeling demonstrated that, when examining predictors simultaneously, marijuana use and psychological victimization predicted sexual behaviors over time for males. For females, marijuana use, and physical and psychological victimization all predicted sexual behaviors over time, with marijuana exerting the strongest effect, particularly among females who also used alcohol. Prevention efforts for adolescent sexual behaviors that increase risk for poor outcomes should include a focus on reducing substance use, particularly marijuana, and the effects of dating violence victimization.

Onset Trajectories of Sexting and Other Sexual Behaviors Across High School: A Longitudinal Growth Mixture Modeling Approach

Sexting is receiving substantial scholarly attention and is now considered commonplace in adolescence. Little is known, however, about the normative contexts and the development of adolescent sexting behavior, including the initiation of sexting in relation to other sexual behaviors. In this study, we used growth mixture modeling to identify classes of onset trajectories for sexual behaviors across high school. Participants included 429 high school students (54% female) who completed annual assessments of sexual behavior over a three-year period. We identified four distinct classes: postponement (9%) with no behaviors other than hand-holding and kissing initiated by Grade 11, gradual onset (44%) with sexting and other sexual behaviors emerging incrementally across high school, continuous onset (32%) with sexting and other sexual behaviors within the first three years of high school, early onset (15%) with initiation of sexting and all other sexual behaviors prior to or by the end of Grade 9. Boys were more likely than girls to be members of the postponement versus gradual onset class, while Black students were more likely than White students to be members of the early versus gradual onset class. Sexting behavior appears to be common in adolescence and co-emerges with genital contact behavior across varying trajectories of sexual development. These findings provide the foundation for contextualizing sexting within normative sexual development. Further, this information can inform efforts to promote sexual health.

Using Composite Scores to Summarize Adolescent Sexual Risk Behavior: Current State of the Science and Recommendations

Composite scores offer the advantage of summarizing across multiple sexual risk behaviors to both simplify results and better capture the influence of core contextual, interpersonal, and intrapersonal dynamics that affect multiple sexual risk behaviors. There is inconsistency in how researchers utilize composite scores with minimal guidance on the advantages and disadvantages of frequently used approaches. Strengths and weaknesses of each approach are discussed in the context of assessing adolescent sexual risk behavior. A latent variable model and three commonly used composites were applied to data combined across four clinical trials (n = 1322; 50% female). Findings suggested that the latent variable approach was limited due to minimal correlations among sexual risk behaviors, that choice of composite had minimal impact on cross-sectional results so long as there is sufficient variability in risk behavior in the sample, but composite choice could impact results from clinical trials particularly for subgroup analyses. There are unique challenges to creating composites of adolescent risk behavior, including the fluidity and infrequency of adolescent sexual relationships that result in many participants reporting no sexual behavior at any given assessment and a low correlation between the number of partners and condomless sex acts. These challenges impede application of data-driven approaches to defining sexual risk composites. Recommendations to improve consistency in reporting include: (1) reporting each type of risk behavior separately prior to forming a composite, (2) aggregating across assessments to increase the chance of observing sexual risk behaviors, and (3) continued work toward a unified definition of adolescent sexual risk behavior that can guide the development of appropriate measurement models.

Patterns of Sexual Behaviors in Young Men Who Have Sex With Men in Mexico

Recent research has documented the importance of understanding the multidimensional nature of sexual risk behavior. However, little is known about patterns of sexual behavior among men who have sex with men (MSM) in Mexico, men who are at greatest risk for HIV and sexually transmitted infections compared to other subpopulations in the country. This study applied latent class analysis to data from a large, HIV-negative sample of 18- to 25-year-old Mexican MSM recruited from a social and sexual networking website (N = 3,722) to uncover multidimensional patterns of sexual behaviors, partner factors, and protective behaviors, and examine how these were associated with health and well-being correlates. We selected a model with seven classes. The most common class included those who reported both insertive and receptive behaviors with more than one partner, but smaller groups of individuals were in classes marked by only insertive or receptive anal sex, romantic relationships, or sexual inactivity. Class membership differed by sexual orientation, age, depressive symptoms, alcohol problems, and self-acceptance, with individuals in a class marked by same-sex relationships generally reporting more positive outcomes. Findings suggest heterogeneity of behaviors among Mexican MSM and the possible efficacy of prevention messages tailored to individuals' specific patterns of sexual behavior.

Individual- and Community-Level Factors in the STD Status of Justice-Involved Youth: Multi-Group, Exploratory Two-Level Analysis

Justice-involved youth display higher prevalence rates of sexually transmitted diseases (STDs), in comparison with youth in the general population, highlighting a critical public health concern. Individual factors are important predictors of STDs, but only provide a partial understanding of this public health issue. Communities experiencing higher levels of disorder and lower levels of cohesion tend to have fewer institutional resources available, which may impact sexual risk behavior and STDs. However, few studies have examined the association between community characteristics and STD prevalence among adolescents. The current study examined community-level (n = 106) characteristics and individual-level attributes in explaining STDs among justice-involved youth (n = 1233: n = 515 female; n = 718 male). At the individual level, results showed older males and those with more drug-related problems were more likely to be STD positive, while females with more sexual partners and those with less drug-related problems were more likely to be STD positive. At the community level, females residing in areas with fewer educated residents were more likely to be STD positive. These gender differences were significant, suggesting a gendered perspective is important for understanding STD infection. The justice system represents a critical opportunity in the treatment and prevention of STDs for youth.

A Multidimensional Approach to Assessing Infectious Disease Risk: Identifying Risk Classes Based on Psychological Characteristics

Prevention of infectious diseases depends on health-related behavior, which is often influenced by psychological characteristics. However, few studies assessing health-related behavior have examined psychological characteristics to identify risk groups, and this multidimensional approach might improve disease risk assessment. We aimed to characterize subgroups based on psychological characteristics and examine their influence on behavior and disease risk, using chlamydia as a case study. Selected participants (heterosexuals aged 18–24 years and females aged 18–24 years who had sex with both men and women) in a Dutch longitudinal cohort study (the Mathematical Models Incorporating Psychological Determinants: Control of Chlamydia Transmission (iMPaCT) Study) filled out a questionnaire and were tested for chlamydia (2016–2017). Latent class analysis was performed to identify risk classes using psychological predictors of chlamydia diagnosis. Two classes were identified: class 1 (n = 488; 9% chlamydia diagnosis) and class 2 (n = 325; 13% chlamydia diagnosis). The proportion of participants with high shame, high impulsiveness, and lower perceived importance of health was higher in class 2 than in class 1. Furthermore, persons in class 2 were more likely to be male and to report condomless sex compared with class 1, but the number of recent partners was comparable. Thus, risk classes might be distinguished from each other by psychological characteristics beyond sexual behavior. Therefore, the impact of the same intervention could differ, and tailoring interventions based on psychological characteristics might be necessary to reduce chlamydia prevalence most effectively.

Sexual Partner Types and Incident HIV Infection Among Rural South African Adolescent Girls and Young Women Enrolled in HPTN 068: A Latent Class Analysis

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.

METHODS

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 LCA-identified 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-of-school 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.

CONCLUSION

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.

HIV Care Trajectories as a Novel Longitudinal Assessment of Retention in Care

Consistent engagement in care is associated with positive health outcomes among people living with HIV (PLWH). However, traditional retention measures ignore the evolving dynamics of engagement in care. To understand the longitudinal patterns of HIV care, we analyzed medical records from 2008 to 2015 of PLWH ≥ 18 years-old receiving care at a public, hospital-based HIV clinic (N = 2110). Using latent class analysis, we identified five distinct care trajectory classes: (1) consistent care (N = 1281); (2) less frequent care (N = 270); (3) return to care after initial attrition (N = 192); (4) moderate attrition (N = 163); and (5) rapid attrition (N = 204). The majority of PLWH in Class 1 (73.9%) had achieved sustained viral suppression (viral load ≤ 200 copies/mL at last test and > 12 months prior) by study end. Among the other care classes, there was substantial variation in sustained viral suppression (61.1% in Class 2 to 3.4% in Class 5). Care trajectories could be used to prioritize re-engagement efforts.

Prevalence of Sexual Initiation Before Age 13 Years Among Male Adolescents and Young Adults in the United States

IMPORTANCE

Despite similar sexual activity rates among male and female adolescents, males are more likely to have their first sexual intercourse before age 13 years. The developmental needs and pathways to healthy trajectories for young males remain unknown.

OBJECTIVE

To examine the prevalence of sexual intercourse before age 13 years among male adolescents; the variation by race/ethnicity, location, and maternal educational level; and the wantedness of this first sexual experience.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analysis was conducted from September 2017 to June 2018, using pooled 2011, 2013, and 2015 data from the school-based Youth Risk Behavior Surveillance System (YRBSS) and the 2006 to 2015 data of males aged 15 to 24 years from the household-based National Survey of Family Growth (NSFG). The percentage of males reporting sexual onset before age 13 years was estimated using survey-weighted logistic regression to test for differences by race/ethnicity within each national survey and within metropolitan areas (for YRBSS, high school and middle school samples). Among NSFG survey respondents, differences in wantedness of first sexual intercourse by age at first sexual intercourse were examined, along with the associations between sexual initiation and socioeconomic covariates.

MAIN OUTCOMES AND MEASURES

Sexual onset before age 13 years.

RESULTS

Data from a total of 19 916 male high school students (from YRBSS) and 7739 males aged 15 to 24 years (from NSFG) were included in the analysis. The sample was largely composed of non-Hispanic white males: 8789 (57.1%) from the YRBSS and 3737 (58.0%) from the NSFG. Sexual onset before age 13 years was reported nationally by 7.6% (95% CI, 6.8%-8.4%) of male high school students and 3.6% (95% CI, 3.0%-4.2%) of males aged 15 to 24 years. The proportion of male students who reported having sexual intercourse before age 13 years varied across metropolitan sites, from 5% (95% CI, 4%-7%) in San Francisco, California, to 25% (95% CI, 23%-28%) in Memphis, Tennessee, with elevated rates among non-Hispanic black and Hispanic males in most metropolitan areas. In the NSFG data set, respondents whose mothers had a college degree or higher educational level were statistically significantly less likely (OR, 0.31; 95% CI, 0.19-0.49) to report having sexual intercourse before age 13 years compared with those whose mothers did not have a college degree. Among males who reported having their first sexual experience before age 13 years, 8.5% (95% CI, 3.8%-17.8%) described their first sexual intercourse as unwanted.

CONCLUSIONS AND RELEVANCE

Rates of sexual onset before age 13 years among young males varied by race/ethnicity, location, and maternal educational level, presenting important implications for the provision of early, inclusive, and comprehensive sex education and sexual and reproductive health care to male children and adolescents.

Examining the Effects of an Adolescent Pregnancy Prevention Program by Risk Profiles: A More Nuanced Approach to Program Evaluation

PURPOSE

The objective of the study was to examine whether latent class analysis (LCA) could (1) identify distinct subgroups of youth characterized by multiple risk and protective factors for early sexual initiation and (2) allow for a more nuanced assessment of the effects of a middle school program to prevent teen pregnancy/HIV/sexually transmitted infection.

METHODS

LCA was applied to data from the baseline (seventh grade) sample of 1,693 sexually inexperienced students participating in a randomized controlled trial of It's Your Game…Keep It Real in Harris County, Texas. Multilevel analysis was applied within subgroups defined by the latent classes to assess for potential differential program effects.

RESULTS

LCA identified 3 distinct profiles of youth: family disruption, other language household, and frequent religious attendance. Multilevel analyses found differential effects of the program across these profiles with a significant and substantial reduction (30%) in initiation of vaginal sex by ninth grade for students in the family disruption profile only.

CONCLUSIONS

Application of LCA may hold promise for conducting more nuanced evaluations and refinements of behavior change interventions for youth.

Patterns of Sexual Behavior and Sexually Transmitted Infections in Young Men Who Have Sex With Men

PURPOSE

Young men who have sex with men (MSM) are at an increased risk for sexually transmitted infections (STIs). Recent research has documented the importance of understanding the multidimensional nature of sexual risk behavior; however, little is known about how multidimensional patterns of sexual behavior among MSM may be associated with STIs.

METHOD

This study applies latent class analysis to data from a large, HIV- sample of 18- to 25-year-old MSM recruited from social and sexual networking Web sites (N = 5965; 76% white, 11% Latino, 5% black, 4% Asian, 4% other; 74% homosexual, 21% bisexual, 1% heterosexual, 3%, unsure/questioning 1% other) to uncover multidimensional patterns of past-year sexual behaviors, partner factors, and protective behavior and their associations with self-reported STI diagnosis.

RESULTS

We selected a model with 8 classes, with nearly half of participants belonging to a class marked by multiple behaviors with more than 1 partner, and smaller numbers of individuals in classes with a smaller number of behaviors, romantic relationships, and sexual inactivity. Class membership was associated with recent STI diagnosis, with classes marked by no penetrative sex or receptive anal sex with consistent condom use having lower prevalence than those with inconsistent condom use, including those engaging in only insertive anal sex.

CONCLUSIONS

Findings suggest heterogeneity of behaviors within MSM and that prevention messages may be more effective if they are tailored to individuals' patterns of sexual behavior, as well as demographic and sociocontextual factors.

Love with HIV: A Latent Class Analysis of Sexual and Intimate Relationship Experiences Among Women Living with HIV in Canada

Love remains hidden in HIV research in favor of a focus on risk. Among 1424 women living with HIV in Canada, we explored (1) whether eight facets of sex and intimacy (marital status, sexual activity, physical intimacy, emotional closeness, power equity, sexual exclusivity, relationship duration, and couple HIV serostatus) may coalesce into distinct relationship types, and (2) how these relationship types may be linked to love as well as various social, psychological, and structural factors. Five latent classes were identified: no relationship (46.5%), relationships without sex (8.6%), and three types of sexual relationships-short term (15.4%), long term/unhappy (6.4%), and long term/happy (23.2%, characterized by equitable power, high levels of physical and emotional closeness, and mainly HIV-negative partners). While women in long-term/happy relationships were most likely to report feeling love for and wanted by someone "all of the time," love was not exclusive to sexual or romantic partners and a sizeable proportion of women reported affection across latent classes. Factors independently associated with latent class membership included age, children living at home, sexism/genderism, income, sex work, violence, trauma, depression, HIV treatment, awareness of treatment's prevention benefits, and HIV-related stigma. Findings reveal the diversity of women's experiences with respect to love, sex, and relationships and draw attention to the sociostructural factors shaping intimate partnering in the context of HIV. A nuanced focus on promoting healthy relationships and supportive social environments may offer a more comprehensive approach to supporting women's overall sexual health and well-being than programs focused solely on sexual risk reduction.

The Influence of Parent and Parent-Adolescent Relationship Characteristics on Sexual Trajectories into Adulthood

To examine sexual partner acquisition into young adulthood and to explore what characteristics of the adolescent family context might predict this change, we used growth curve modeling to examine data from a nationally representative sample of adolescents followed longitudinally over 13 years through young adulthood (N = 5385). Growth curve modeling allowed us to treat the outcome as a dynamic variable and to examine 10 potential predictors of change while accounting for the nested nature of the data. Six family characteristics emerged as predictors of mean number of partners and rate of partner acquisition, while accounting for three significant adolescent predictors. Living in a single-parent or blended family and general communication about sex predicted higher lifetime number of sexual partners in young adulthood. Parent religiosity, parent disapproval of adolescent engagement in sex, and parent-adolescent connectedness were predictive of lower lifetime number of sexual partners. By following participants into their late twenties and early thirties, we were able to detect changes in the impact of early family factors that are not apparent in studies restricted to adolescents and emerging adults. For example, parent education, parent disapproval, and parent-adolescent connectedness were associated with higher rates of partner acquisition at age 23, but faster deceleration in partner acquisition as time progressed. Communication about negative consequences of sex was not predictive, regardless of whether it was "on time" (before sexual intercourse) or not. These results reveal that parents have significant, and sometimes unexpected, influence on their children's sexual behavior that persists well into adulthood.

Online Sexual Experiences Predict Subsequent Sexual Health and Victimization Outcomes Among Female Adolescents: A Latent Class Analysis

Adolescents' online sexual experiences (e.g., pornography use, sexual chatting, sexualized social media use, and nude image exchange) provide a new context for sexual socialization. Traditionally, online sexual experiences are often aggregated averages, which neglect their complexity and fail to identify individual differences in the experience. Moreover, the lack of longitudinal research in this area has failed to determine if these experiences predict later offline sexual health and violence outcomes. An analysis of two waves of surveys completed by ethnically and socioeconomically diverse female adolescents (N = 296; 49% maltreated; aged 14-16 years) participating in a larger cross-sequential study was conducted to address these gaps. Established latent classes from the prerequisite study of online sexual experiences at Time 1 were Online Abstinent (low probability of any online sexual experiences), Online Inclusive (high probability of all online sexual experiences), Attractors (high probability of attracting attention from others), and Seekers (high probability of seeking out sexual content and interaction). Class membership uniquely predicted HIV risk, number of physically violent romantic partners, and the occurrence of sexual assault at Time 2. Although membership in risker online sexual experience classes predicted later offline risk and victimization, this was especially true for maltreated participants. These findings demonstrate the advantages of examining online sexual experiences in a way that emphasizes their complexity and individual differences in influential susceptibility.