Contributions of the Fragile Families and Child Wellbeing Study to Child Development

We describe the promise of the Fragile Families and Child Wellbeing Study (FFCWS) for developmental researchers. FFCWS is a birth cohort study of 4,898 children born in 1998–2000 in large US cities. This prospective national study collected data on children and parents at birth and during infancy (age 1), toddlerhood (age 3), early childhood (age 5), middle childhood (age 9), adolescence (age 15), and, in progress, young adulthood (age 22). Though FFCWS was created to understand the lives of unmarried parent families, its comprehensive data on parents, children, and contexts can be used to explore many other developmental questions. We identify six opportunities for developmentalists: ( a) analyzing developmental trajectories, ( b) identifying the importance of the timing of exposures for later development, ( c) documenting bidirectional influences on development, ( d) understanding development in context, ( e) identifying biological moderators and mechanisms, and ( f) using an urban-born cohort that is large, diverse, and prospective.

Influences of Maternal Parenting Stress on Child Behavior Problems: Examining Harsh and Positive Parenting as Mediators

Extant research demonstrates associations between parenting stress and child internalizing and externalizing problems, with evidence that parenting behaviors may mediate these associations; however, few studies have been longitudinal. The current study tested whether harsh and positive parenting mediated associations between maternal parenting stress and child internalizing and externalizing problems. Data from the Fragile Families and Child Wellbeing Study were utilized, with 2,606 families who completed the year nine wave included (37% less than high school; 60.2% married/cohabitating; 50% Black, non-Hispanic; 24% Hispanic; and 26% White, non-Hispanic). Analyses revealed parenting stress at age three was significantly associated with higher child internalizing and externalizing problems at age nine. Further, positive but not harsh parenting mediated the link between parenting stress and externalizing problems. Parenting did not mediate the association between parenting stress and internalizing problems. Findings suggest harsh and positive parenting differentially explains associations between parenting stress and child internalizing and externalizing problems.

Re-thinking Stepfathers’ Contributions: Fathers, Stepfathers, and Child Wellbeing

Using data from a contemporary cohort of children, we revisit the question of whether children benefit from being close to and engaging in activities with a stepfather. We deploy the Fragile Families and Child Wellbeing Study, a birth cohort study of nearly 5000 children born in US cities in 1998–2000, with a large oversample of nonmarital births. We explore the relationships between stepfathers’ closeness and active engagement and youth’s internalizing and externalizing behaviors and school connectedness at ages 9 and 15 for between 550 and 740 children (depending on the wave) with stepfathers. We find that the emotional tenor of the relationship and level of active engagement between youth and their stepfathers are associated with reduced internalizing behaviors and higher school connectedness. Our findings suggest that stepfathers’ roles seem to have evolved in ways that are more beneficial to their adolescent stepchildren than was previously the case.

Low Self-Control and Perceptions of Procedural Justice Among Urban-Born Youth: The Moderating Role of Officer Intrusiveness

The current study examines whether the link between low self-control and perceptions of procedural justice among urban-born youth is contingent on acts of officer intrusiveness. Data come from the Fragile Families and Child Wellbeing Study and are restricted to youth reporting lifetime police stops at Year 15 ( N = 918). Findings reveal that the association between low self-control and diminished perceptions of procedural justice is significantly moderated by officer intrusiveness. To be precise, low self-control became more relevant in diminished perceptions of procedural justice as officer intrusiveness decreased. The findings carry implications for police-citizen interactions, including the training of police officers in developmental science and how low self-control may shape youth perceptions of police encounters.

The Intersection Between Sex and Race in Understanding Substance Co-Use Patterns in Adolescents From the Fragile Families Study

The current study examined the prevalence of alcohol, cigarette, and cannabis co-use among a longitudinal cohort of youth predominately born to single-parent families. Data were drawn from wave six of the Fragile Families and Child Wellbeing Study ( N = 2976; M age = 15.6; 49% female; 53% non-Hispanic Black, 27% Hispanic, 20% White). Adolescents’ reports of their past 30-day use of alcohol, cigarettes, and cannabis were used to construct eight mutually exclusive use groups. Multinomial logistic regressions adjusting for sociodemographic factors revealed that Black adolescents were at lower relative risk of using Alcohol Only compared to White adolescents. Black males were at greater relative risk of using Cannabis Only than both White males and Black females. Finally, Hispanic males were at a marginally increased relative risk of co-using Alcohol and Cannabis compared to White males. Prevention efforts targeting Black and Hispanic males’ use of cannabis (both alone and in combination with alcohol) may be beneficial.

InterModel Vigorish (IMV): A novel approach for quantifying predictive accuracy when outcomes are binary

Understanding the ``fit'' of models meant to predict binary outcomes has been a long-standing problem. We propose a novel metric---the InterModel Vigorish (IMV)---for quantifying the value of change in predictive accuracy between two systems in the case of a binary outcome. The metric is based on an analogy to well-characterized physical systems with tractable probabilities. We first translate a baseline prediction of some binary outcomes into a statement about a canonical system---weighted coins---by equating the entropy of the two systems. We then use the weighted coin for a baseline prediction to establish a fair bet. For a second predictive system that we want to gauge relative to the baseline, we use the notion of expected winnings from a single-blind bet wherein the second weighted coin has replaced the first (the opposing player being blinded to this replacement). The resulting quantity has a scale that is both generally applicable and not dependent on the magnitude of the baseline prediction; moreover, it is always a statement about the change in fit relative to some baseline (which can simply be the prevalence) whereas other metrics (e.g., AUC) are stand-alone measures that need to be further manipulated to yield indices related to differences in fit across models. We illustrate the properties of this metric in simulations, and the value of it in empirical applications related to health, political affiliation, and item responses. We also reconsider results from the recent Fragile Families Challenge using the IMV metric.

Differentially methylated regions and methylation QTLs for teen depression and early puberty in the Fragile Families Child Wellbeing Study

The Fragile Families Child Wellbeing Study (FFCWS) is a longitudinal cohort of ethnically diverse and primarily low socioeconomic status children and their families in the U.S. Here, we analyze DNA methylation data collected from 748 FFCWS participants in two waves of this study, corresponding to participant ages 9 and 15. Our primary goal is to leverage the DNA methylation data from these two time points to study methylation associated with two key traits in adolescent health that are over-represented in these data: Early puberty and teen depression. We first identify differentially methylated regions (DMRs) for depression and early puberty. We then identify DMRs for the interaction effects between these two conditions and age by including interaction terms in our regression models to understand how age-related changes in methylation are influenced by depression or early puberty. Next, we identify methylation quantitative trait loci (meQTLs) using genotype data from the participants. We also identify meQTLs with epistatic effects with depression and early puberty. We find enrichment of our interaction meQTLs with functional categories of the genome that contribute to the heritability of co-morbid complex diseases. We replicate our meQTLs in data from the GoDMC study. This work leverages the important focus of the FFCWS data on disadvantaged children to shed light on the methylation states associated with teen depression and early puberty, and on how genetic regulation of methylation is affected in adolescents with these two conditions.