This article reviews the origins and use of the terms quasi-experiment and natural experiment. It demonstrates how the terms conflate whether variation in the independent variable of interest falls short of random with whether researchers find, rather than intervene to create, that variation. Using the lens of assignment--the process driving…

Psychologists are emphasizing the importance of predictive conclusions. Machine learning methods, such as supervised neural networks, have been used in psychological studies as they naturally fit prediction tasks. However, we are concerned about whether neural networks fitted with random datasets (i.e., datasets where there is no relationship…

A linear model is often used to find the effect of a binary treatment D on a noncontinuous outcome Y with covariates X. Particularly, a binary Y gives the popular "linear probability model (LPM)," but the linear model is untenable if X contains a continuous regressor. This raises the question: what kind of treatment effect does the…

Understanding the factors associated with variation in the implementation of educational programs has emerged as a key research focus, in an effort to identify how promising programs can be scaled up across their targeted contexts. The current study explored demographic-related variation in program dosage using a novel source of implementation…

Multi-site randomized controlled trials (RCTs) provide unbiased estimates of the average impact in the study sample. However, their ability to accurately predict the impact for individual sites outside the study sample, to inform local policy decisions, is largely unknown. To extend prior research on this question, we analyzed six multi-site RCTs…

Longitudinal survey and experimental research is essential for understanding psychological and economic processes, but attrition is a concern. We examine attrition in a 2016 longitudinal randomized controlled trial of more than 13,000 prospective U.S. homeowners, in which participants were invited to up to seven online surveys delivered every two…

The current study examined predictors of outcomes across two school clinician-delivered treatments (i.e., treatment as usual [TAU] or modular cognitive-behavioral therapy [M-CBT]) for youth with anxiety disorders. Predictors reflected two broad domains -- therapist factors (i.e., education, years of experience, therapeutic orientation, work…

Recent methods have sought to improve precision in randomized controlled trials (RCTs) by utilizing data from large observational datasets for covariate adjustment. For example, consider an RCT aimed at evaluating a new algebra curriculum, in which a few dozen schools are randomly assigned to treatment (new curriculum) or control (standard…

Background/Context: Early childhood education research has consistently found evidence of immediate, positive effects on developmental outcomes. Despite these strong initial benefits, follow-up analyses often reveal that these effects fadeout in the years following participation (e.g., Bailey et al., 2017, Clements et al., 2013; Lipsey et al.…

Background: It has become increasingly important to shift education research and programming from a deficit focused perspective to a positive youth development perspective in order to identify and promote factors that support students' positive functioning and outcomes. One outgrowth of positive youth development is Positive Mental Health (PMH),…

Background: Offspring of anxious parents are at increased risk for developing anxiety disorders. There is a need to identify which youth are at greatest risk for disorder onset in this population. Objective: This study prospectively examined several theory-based family and parent characteristics (e.g., family conflict, parental over-control,…

Anxiety interventions involving social skills training and CBT for youth with ASD have shown promise, but few studies have examined the effects on social functioning or the maintenance of treatment gains. This study evaluated change in social skills during a randomized controlled trial of CBT and during the 1-year follow-up for 25 adolescents with…

Based on a one-year longitudinal experimental study with 3,782 kindergarten school children across 15 countries, this article examines the association between prayer and happiness. Results show that the post-test scores on the faces scale were higher for the participant group who had taken the prayer lessons vis-à-vis the comparison group.…

Despite schools increasingly adopting multitiered systems of support (MTSS) for prevention and intervention of mental health concerns, many are slow to adopt universal mental health screening (UMHS), a core MTSS feature, due to concerns about their limited capacity to meet the needs of all identified. In this study, we examined differences in the…

Background: Native Hawaiians and other Pacific Islanders have high rates of overweight and obesity compared with other ethnic groups in Hawai'i. Effective weight loss and weight loss-maintenance programs are needed to address obesity and obesity-related health inequities for this group. Aims: Compare the effectiveness of a 9-month, worksite-based,…