The Campbellian validity typology has been used as a foundation for outcome evaluation and for developing evidence-based interventions for decades. As such, randomized control trials were preferred for outcome evaluation. However, some evaluators disagree with the validity typology's argument that randomized controlled trials as the best design…

Computation is foundational to learning many mathematics concepts, as well as a functional skill in everyday life. Yet students with autism spectrum disorder (ASD) often have challenges in learning computation skills. The current study aimed to provide quantitative and descriptive analyses of single-case experimental studies on computation…

Teachers can use a variety of classroom management practices to help foster a classroom environment in which all students can learn. "Good Behavior Game" is a specific classroom management strategy that aims to improve social skills, minimize disruptive behaviors, and create a positive learning environment. Teachers place students into…

Teachers can use a variety of classroom management practices to help foster a classroom environment in which all students can learn. "Good Behavior Game" is a specific classroom management strategy that aims to improve social skills, minimize disruptive behaviors, and create a positive learning environment. Teachers place students into…

School counselors are tasked with many activities, including demonstrating the effectiveness of interventions they use with students. The American School Counselor Association recommends that school counselors include assessment, appraisal, and evaluation of delivery and program management in their school counseling program. Single-case research…

Evaluators of education interventions are increasingly designing studies to detect impacts much smaller than the 0.20 standard deviations that Cohen characterized as "small." While the need to detect smaller impacts is based on compelling arguments that such impacts are substantively meaningful, the drive to detect smaller impacts may…

This article reviews important statistical methods for estimating the impact of interventions on outcomes in education settings, particularly programs that are implemented in field, rather than laboratory, settings. We begin by describing the causal inference challenge for evaluating program effects. Then four research designs are discussed that…

Education decisionmakers need access to the best evidence about the effectiveness of education interventions, including practices, products, programs, and policies. It can be difficult, time consuming, and costly to access and draw conclusions from relevant studies about the effectiveness of interventions. The What Works Clearinghouse (WWC)…

The major aim of this manuscript is to bring together two important topics that have recently received much attention in child and adolescent research, albeit separately from each other: single-case experimental designs and statistical mediation analysis. Single-case experimental designs (SCEDs) are increasingly recognized as a valuable…

Traditional pre-test (TpT)/post-test (PT) and retrospective pre-test (RpT)/post-test (PT) designs are used to collect data on self-reported measures to assess the magnitude of change that occurs from interventions. If measurement invariance does not exist across the measurement occasions within these research designs, it is inappropriate to…

Evaluators of education interventions increasingly need to design studies to detect impacts much smaller than the 0.20 standard deviations that Cohen (1988) characterized as "small." For example, an evaluation of Response to Intervention from the Institute of Education Sciences (IES) detected impacts ranging from 0.13 to 0.17 standard…

Single-case research methods provide the basis for evaluating effective instructional approaches in special education. The purpose of this article is to provide special educators an overview of single-case research methods, with an emphasis on how these designs are used to establish whether an instructional practice relates to improved learner…

Interventions often require multiple decisions to improve outcomes for every student. Whether the decision to implement a practice, tailor an existing protocol, or change approaches, these decisions should be based on individual variables and outcomes via a sequence of treatment. To develop adaptive interventions that have sufficient evidence to…

Using an RD design provides statistically robust estimates while allowing researchers a different causal estimation tool to be used in educational environments where an RCT may not be feasible. Results from External Evaluation of the i3 Scale-Up of Reading Recovery show that impact estimates were remarkably similar between a randomized control…

Underlying all What Works Clearinghouse (WWC) products are WWC Study Review Guides, which are intended for use by WWC certified reviewers to assess studies against the WWC evidence standards. As part of an ongoing effort to increase transparency, promote collaboration, and encourage widespread use of the WWC standards, the Institute of Education…