Demonstration of experimental control is considered a hallmark of high-quality single-case research design (SCRD). Studies that fail to demonstrate experimental control may not be published because researchers are unwilling to submit these papers for publication and journals are unlikely to publish negative results (i.e., the file drawer effect).…

Regression discontinuity designs (RDDs) are considered to be one of the strongest nonexperimental designs available for the purpose of identifying the effects of an intervention. RDD can be used in situations in which assignment to a treatment group is based on a cutoff value on a continuous assignment variable. The impact of the intervention is…

This report summarizes the complex research literature on quantitative methods for assessing how impacts of educational interventions on instructional practices and student learning differ across students, educators, and schools. It also provides technical guidance about the use and interpretation of these methods. The research topics addressed…

This methodological brief is designed to provide both program operators and researchers with practical advice about how to assess a program's implementation and impact. Adapted from an article that first appeared in "The Handbook of Youth Mentoring" (DuBois and Karcher, ed. 2005), the brief focuses on the evaluation of mentoring programs, but the…

Animated pedagogical agents (APAs) have the potential to provide one-on-one, just-in-time instruction, guidance or mentoring in classrooms where such individualized human interactions may be infeasible. Much current APA research focuses on a wide range of design variables tested with small samples or in laboratory settings, while overlooking…

A meta-analysis was conducted on 44 educational studies that used either a (labelled) Hawthorne control group, a manipulation of Hawthorne effects, or a group designed to control for the Hawthorne effect. The sample included published journal articles, ERIC documents or unpublished papers, and dissertations. The studies were coded on 20 variables,…

This article discusses research design problems peculiar to work with intellectually disabled subjects, such as discrepancies in uses of control groups and mental age matching, definitions of subject groups and variability within and between subject groups. Suggestions for minimizing these problems are made and alternative methodologies offered.…

This paper identifies methodological and practical problems in studies of child maltreatment, including developing classification schemes for multiple forms of maltreatment; distinguishing between chronic maltreatment and isolated incidents; choosing criteria for selecting comparison groups; determining whether comparison groups have experienced…

Ninety-two research reports involving specifically language-impaired subjects were reviewed. Analysis showed few consistent trends with respect to subject selection, subject description, and the number and types of control groups. The importance of more complete subject descriptions and matching criteria for control groups is discussed.…

There has been an increasing emphasis in educational policies, practices and professional development on the capacity of educational leadership to exert a causal impact on student cognitive and non-cognitive outcomes. If the strict criteria of counterfactual causality are adhered to no causal inference could be made about the effects of…

This article examines the status of behavioral research on genetic mental retardation syndromes and finds that the field continues to struggle with three methodological issues: (1) how to think about control or contrast groups, (2) the interplay of behavioral phenotypes with development and other within-group variations, and (3) the efficacy of…

This is a checklist of key items to get right when conducting a randomized controlled trial to evaluate an educational program or practice ("intervention"). It is intended as a practical resource for researchers and sponsors of research, describing items that are often critical to the success of a randomized controlled trial. A significant…

This study explores the use of the adjunct question paradigm in self-instruction and distance education materials. The subjects were 187 high school students who read text passages and answered one high level (implication or inference) or low level (verbatim or paraphrase) question. These questions were either inserted in the text or massed at the…

This study investigated the effects of different structures of a synthesizer and formats of the generality component on the application and remember levels of learning. Seventy-three undergraduates participated. Four treatment groups were formed by combining two types of structure (complete versus partial) with two types of format in generality…

Using the Component Display Theory as an analyzing tool, this study compared the effects of expository and discovery methods of instruction on two learning outcomes, application and transfer. One hundred ninth grade students in each of four earth science classes were randomly assigned to five groups--four experimental groups designed to test four…