Controlling Contamination Bias in Child Maltreatment Research

Contamination occurs in many different experimental designs outside the field of child maltreatment. In this project, contamination refers to the presence of child maltreatment in an already established, non-child maltreatment comparison condition. Research has shown that failure to detect and control contamination biases effect size estimates for child maltreatment outcomes and leads to variation in the significance and magnitude of those estimates within and across studies, increasing the chances of discovery and replication failures. The Detecting and Controlling Contamination Bias Project (Shenk, PI; Shores and Ram, Co-I’s) is supported by an NIH award (R03HD104739) examining contamination in prospective cohort studies of child maltreatment. 

The current project is using existing data from a large, multi-site, multi-wave prospective cohort study of confirmed child maltreatment (N=1354) to accomplish two specific aims: 1) estimate the prevalence of contamination, defined as any self-reported instance of child maltreatment by members of the established comparison condition, and 2) test five different statistical approaches for reducing bias in risk estimates for child behavior problems attributable to contamination.

 Finally, this project will conduct extensive data simulations based on these results to extend inferences across different research conditions, including variations in sample size, contamination prevalence, statistical power, and effect size magnitude. The end product of this project will be to disseminate to the larger scientific field the optimal methods for detecting and controlling contamination bias across a range of research conditions in order to minimize variation in the significance and magnitude of effect size estimates reported across prospective studies.  T32 Fellows will have the opportunity to generate, execute, and report results from statistical models aiming to establish the optimal detection and control of contamination. Statistical models where Fellows can receive training include, multi-level modeling, propensity score matching, and augmented synthetic controls. 

Child Maltreatment and Cardiovascular Disease Risk

This grant (R01HL158577; PI: Schreier) takes advantage of a large, well-characterized, prospective cohort of youth who were recently investigated for child maltreatment and comparison youth without a maltreatment history to better understand the physiological mechanisms between early adversity and cardiovascular diseases risk. By taking advantage of detailed assessments of immune function coupled with administrative health care records and thorough behavioral and psychosocial assessments, we will prospectively examine links between child maltreatment and cardiovascular disease risk, with the hopes of informing future prevention and intervention efforts.

Epigenetic and Cognitive Aging Project (ECAP)

ECAP (Shenk, PI; O’Donnell, Sliwinski, Ram, and Noll, Co-I’s) is supported by an NIH award (R01AG059682) examining the impact of child maltreatment on epigenetic age acceleration, a cross-tissue index of the biological aging of cells that is derived from DNA methylation across the genome and has added explanatory power of adulthood health beyond chronological age. This project will first examine epigenetic age acceleration and its relation to mid-life cognitive function in the Female Growth and Development Study (FGDS), a 30-year prospective cohort study of the long-term effects of childhood sexual abuse. The FGDS cohort also provides an unprecedented opportunity to test the mediational properties of glucocorticoid remodeling occurring over the 20 years following exposure to substantiated child sexual abuse on epigenetic age acceleration as well as the risks associated with epigenetic age acceleration and a comprehensive assessment of cognitive function at mid-life. Once statistical models of epigenetic age acceleration and cognitive outcomes are developed using data from the FGDS discovery cohort, they will be exported for replication in independent, international cohorts to extend models to more diverse samples, including older ages and alternative cognitive outcomes (e.g. mild cognitive impairment). Results will inform precision-based efforts at preventing, delaying, or reversing the onset of various cognitive aging outcomes across different points of the lifespan. 

The Life Events and Reactions Study (LEARS)

LEARS is a genetic case-control association study (Shenk, PI: KL2TR000078) examining the genetic and epigenetic mechanisms associated with the onset of psychiatric disorders in the child maltreatment population. Children between the ages of 8 and 15 years of age who have experienced substantiated child maltreatment participated in this study. Biospecimens (oral fluid, buccal swab) collected in this study are being used to generate estimates of variation in DNA and DNA methylation to predict the course and severity of psychiatric symptoms and diagnoses obtained from a structured psychiatric interview. Results from this study will provide insight into the genetic, epigenetic, and psychological contributions for these disorders in the child maltreatment population so that interventions targeting these processes can be developed or applied more effectively. CMT32 Fellows would have the opportunity to examine a variety of epigenetic age acceleration estimates and their relation to a host of psychiatric disorders and symptom severity with the existing data collected in this project. 

Integrating Animal-Assisted Therapy into TF-CBT for Children Exposed to Maltreatment (AAT+TF-CBT)

The AAT+TF-CBT project (Shenk, Co-I) is an NIH-funded (Allen, PI: R21HD091887) randomized feasibility trial examining the tolerability and acceptability of delivering TF-CBT while a service dog is present throughout the active phase of treatment. TF-CBT is one of the few well-established interventions for children experiencing maltreatment and this clinical trial is examining whether introducing a service dog during standard administration of TF-CBT enhances treatment effects above and beyond TF-CBT alone. The laboratory’s contribution to this project is overseeing the collection, editing, and analysis of electrocardiogram data obtained at pre-treatment as well as at strategic sessions during the active treatment phase. Current work on this project involves generating estimates of the respiratory sinus arrhythmia (RSA), an index of parasympathetic control of cardiac activity, in 30-second epochs and modeling within and between session change in RSA as a potential mechanism of action in TF-CBT when treating child maltreatment-related post-traumatic stress disorder (PTSD). Potential opportunities for CMT32 Fellows include modeling RSA reactivity to the Trier Social Stress Test administered at pre-treatment to determine whether such reactivity is related to within-session changes in RSA and PTSD symptom severity at post-treatment.