This article examines the implementation, participation rates, and potential determinants of participation in the digital addiction prevention program "ready4life." A two-arm cluster-randomized trial recruited German vocational students via class-based strategies. Intervention group received 16 weeks of in-app coaching; the control group…

Background: In children with a cleft palate with or without a cleft lip (CP±L), some evidence exists for superior results of high-intensity speech intervention (HISI) compared with low-intensity speech intervention (LISI) on speech and health-related quality of life (HRQoL). However, the existing research often involves small sample sizes.…

Early work experiences are associated with subsequent employment for students with significant disabilities, but they rarely receive such opportunities. This article presents two case studies illustrating a school-based intervention that connected students with significant disabilities to paid work during high school and included training for…

Cluster randomized control trials often incorporate a longitudinal component where, for example, students are followed over time and student outcomes are measured repeatedly. Besides examining how intervention effects induce changes in outcomes, researchers are sometimes also interested in exploring whether intervention effects on outcomes are…

Plausible competing developmental models show similar or identical structural equation modeling model fit indices, despite making very different causal predictions. One way to help address this problem is incorporating outside information into selecting among models. This study attempted to select among developmental models of children's early…

Cluster randomized trials (CRTs) are commonly used to evaluate educational interventions, particularly their effectiveness. Recently there has been greater emphasis on using these trials to explore cost-effectiveness. However, methods for establishing the power of cluster randomized cost-effectiveness trials (CRCETs) are limited. This study…

This article provides evidence about predictive relationships between features of community college interventions and their impacts on student progress. This evidence is based on analyses of student-level data from large-scale randomized trials of 39 (mostly) community college interventions. Specifically, the evidence consistently indicates that…

Power in multilevel models remains an area of interest to both methodologists and substantive researchers. In two-level designs, the total sample is a function of both the number of level-2 (e.g., schools) clusters and the average number of level-1 (e.g., classrooms) units per cluster. Traditional multilevel power calculations rely on either the…

We present findings across three randomized trials of "Descubriendo la Lectura" (DLL), an intervention designed to improve literacy skills of Spanish-speaking first graders struggling with reading. DLL is a one-to-one Spanish-language literacy program lasting 12-20 weeks offered to a school's lowest performing emerging bilingual first…

During the COVID-19 pandemic, the race to find an effective vaccine or treatment saw an 'extraordinary number' of clinical trials being conducted. While there were some key success stories, not all trials produced results that informed patient care. There was a significant amount of waste in clinical research during the pandemic which is said to…

This article examines the risk of crossover contamination in individual-level randomization, a common concern in experimental research, in the context of a large-enrollment college course. While individual-level randomization is more efficient for assessing program effectiveness, it also increases the potential for control group students to cross…

Emergent technologies present platforms for educational researchers to conduct randomized controlled trials (RCTs) and collect rich data on study students' performance, behavior, learning processes, and outcomes in authentic learning environments. As educational research increasingly uses methods and data collection from such platforms, it is…

Emergent technologies present platforms for educational researchers to conduct randomized controlled trials (RCTs) and collect rich data to study students' performance, behavior, learning processes, and outcomes in authentic learning environments. As educational research increasingly uses methods and data collection from such platforms, it is…

Cluster randomized trials are frequently used in educational research for methodological reasons. This study aims to improve the efficiency of cluster randomized trials on computer/information literacy and computational thinking. The study employs a two-level hierarchical linear model to estimate: (1) intraclass correlation coefficients; (2) the…

In education, multisite trials involve randomization of pupils into intervention and comparison groups within schools. Most analytical models in multisite educational trials ignore that the impact of an intervention may be school dependent. This study investigates the impact of statistical models on the uncertainty associated with an effect size…