George W. Howe

Nature and Nurture: Genetic Contributions to Measures of the Family Environment.

Research suggests that measures of the family environment show genetic effects when treated as phenotypes in behavioral genetic analyses. We explored this issue as part of the Nonshared Environment in Adolescent Development project using diverse questionnaire measures of parent-child and sibling interactions. The sample consisted of 707 pairs of siblings from 10 to 18 years of age in a novel design (identical and fraternal twins and full siblings in nondivorced families, and full, half, and unrelated siblings in stepfamilies). Model-fitting analyses yielded evidence for significant genetic effects for 15 of 18 composite measures. On average, more than a quarter of the variance of these environmental measures can be accounted for by genetic differences among children

Standards of Evidence for Efficacy, Effectiveness, and Scale-up Research in Prevention Science: Next Generation

A decade ago, the Society of Prevention Research (SPR) endorsed a set of standards for evidence related to research on prevention interventions. These standards (Flay et al., Prevention Science 6:151–175, 2005) were intended in part to increase consistency in reviews of prevention research that often generated disparate lists of effective interventions due to the application of different standards for what was considered to be necessary to demonstrate effectiveness. In 2013, SPR’s Board of Directors decided that the field has progressed sufficiently to warrant a review and, if necessary, publication of “the next generation” of standards of evidence. The Board convened a committee to review and update the standards. This article reports on the results of this committee’s deliberations, summarizing changes made to the earlier standards and explaining the rationale for each change. The SPR Board of Directors endorses “The Standards of Evidence for Efficacy, Effectiveness, and Scale-up Research in Prevention Science: Next Generation.”

Can prevention trials test theories of etiology

This paper addresses the issue of whether prevention research methods, particularly those involving randomized prevention trials, can be used to test theories concerning the etiology of psychopathology. Based on recent empirical and theoretical work in developmental psychopathology, three aspects of etiologic theory are discussed: risk and protective mechanisms, the integration of environmental and genetic factors, and patterns of developmental progression in psychopathology across the life span. It is suggested that integration of prevention trial methods with methods from passive correlational designs, behavioral genetics, and longitudinal studies allows for unique opportunities to test hypotheses about etiology. Empirical literature on the development and prevention of internalizing disorders, particularly depression, is presented to support this argument. Limitations of prevention trials for testing theory are also reviewed.

Job Loss and Depressive Symptoms in Couples: Common Stressors, Stress Transmission, or Relationship Disruption?

Three models of the linkage between stressors and depressive symptoms were tested in 252 couples after job loss. Data were analyzed to test whether depressive symptoms in both members of the couple were due to common stressors, the transmission of stress from 1 member to the other, or changes in relationship quality. Evidence was found for all 3 processes. Common stressors influenced depressive symptoms in both partners. Anger and depressive symptoms of each partner partially mediated these effects on the other partner, as did reductions in relationship quality. Findings suggest that interventions to help couples cope with the aftermath of job loss may hold promise for preventing depressive reactions to stress.

Microtrial Methods for Translating Gene-environment Dynamics into Preventive Interventions

Genetically informed research on behavioral outcomes holds substantial promise for guiding efforts to enhance the efficacy and effectiveness of preventive interventions, but it also poses considerable challenges given the complexities of the dynamic interplay between genes and environment. This paper introduces a relatively uncommon research design, called microtrials, to provide a means of translating basic research findings into prevention trials, particularly through introducing genetic effects into prevention models. Microtrials are defined as randomized experiments testing the effects of relatively brief and focused environmental manipulations designed to suppress specific risk mechanisms or enhance specific protective mechanisms, but not to bring about full treatment or prevention effects in distal outcomes. Microtrial methods are described in detail, with discussion of their unique advantages for translating this knowledge base into prevention research. We end by raising several issues to consider when constructing genetically sensitive microtrials.

Maternal depressive symptoms and child sleep: Models of mutual influence over time

The aim of the research was to test hypotheses concerning the associations between maternal depressive symptoms and child sleep using longitudinal data to examine possible predictive pathways. Data from the National Institute of Child Health and Human Development Study of Early Child Care with 1222 children studied from 1 to 36 months of age were analyzed to examine: effects on trajectories over time, and phase-specific effects over three defined age periods (6 to 15, 15 to 24, and 24 to 36 months). Child sleep was found to influence maternal depressive symptoms only for the 15- to 24-month age period, where, contrary to expectation, longer duration of child awakenings predicted decreased maternal depressive symptoms. Maternal depressive symptoms were found to predict an increased frequency of child awakenings across the 15- to 24-month age period only. In contrast, maternal depressive symptoms were found to significantly predict increased duration of child awakenings both for the 3-year trajectory and across the 15- to 24- and 24- to 36-month age periods. Additional research is needed to clarify the mechanisms by which maternal depressive symptoms predict increased duration of child awakenings.

The Role of Behavior Observation in Measurement Systems for Randomized Prevention Trials

The role of behavior observation in theory-driven prevention intervention trials is examined. A model is presented to guide choice of strategies for the measurement of five core elements in theoretically informed, randomized prevention trials: (1) training intervention agents, (2) delivery of key intervention conditions by intervention agents, (3) responses of clients to intervention conditions, (4) short-term risk reduction in targeted client behaviors, and (5) long-term change in client adjustment. It is argued that the social processes typically thought to mediate interventionist training (Element 1) and the efficacy of psychosocial interventions (Elements 2 and 3) may be powerfully captured by behavior observation. It is also argued that behavior observation has advantages in the measurement of short-term change (Element 4) engendered by intervention, including sensitivity to behavior change and blinding to intervention status.

Methods for Synthesizing Findings on Moderation Effects Across Multiple Randomized Trials

This paper presents new methods for synthesizing results from subgroup and moderation analyses across different randomized trials. We demonstrate that such a synthesis generally results in additional power to detect significant moderation findings above what one would find in a single trial. Three general methods for conducting synthesis analyses are discussed, with two methods, integrative data analysis and parallel analyses, sharing a large advantage over traditional methods available in meta-analysis. We present a broad class of analytic models to examine moderation effects across trials that can be used to assess their overall effect and explain sources of heterogeneity, and present ways to disentangle differences across trials due to individual differences, contextual level differences, intervention, and trial design.

Adolescents' relationships to siblings and mothers: A multivariate genetic analysis.

Research has consistently demonstrated that childrens behavior toward their siblings tends to resemble interactions occurring in the parent-child relationship. This study examined the relative contributions of genetic and environmental influences to the covariation between sibling relationships and mother-adolescent relationships. Reported and observed family interactions were assessed for 719 same-sex sibling pairs of varying degrees of genetic relatedness. The covariance between mother-adolescent and sibling interactions was decomposed into genetic, shared, and nonshared environmental components. The overlapping effects of shared environment on the two relationship subsystems explained most of the covariance. Smaller but significant genetic and nonshared environmental effects were also found. The consistency of these findings with family processes, such as modeling, is discussed.

Advancing Science Through Collaborative Data Sharing and Synthesis

The demand for researchers to share their data has increased dramatically in recent years. There is a need to replicate and confirm scientific findings to bolster confidence in many research areas. Data sharing also serves the critical function of allowing synthesis of findings across trials. As innovative statistical methods have helped resolve barriers to synthesis analyses, data sharing and synthesis can help answer research questions that cannot be answered by individual trials alone. However, the sharing of data among researchers remains challenging and infrequent. This article aims to (a) increase support for data sharing and synthesis collaborations among researchers to advance scientific knowledge and (b) provide a model for establishing these collaborations using the example of the ongoing National Institute of Mental Health’s Collaborative Data Synthesis on Adolescent Depression Trials. This study brings together datasets from existing prevention and treatment trials in adolescent depression, as well as researchers and stakeholders, to answer questions about “for whom interventions work” and “by what pathways interventions have their effects.” This is critical to improving interventions, including increasing knowledge about intervention efficacy among minority populations, or what we call “scientific equity.” The collaborative model described is relevant to fields with research questions that can only be addressed by synthesizing individual-level data.