The motivation for this paper is the authors' recent work on several randomized control trials in which they found the primary result, which averaged across subgroups or sites, to be moderated by demographic or site characteristics. They are led to examine a distinction that the Institute of Education Sciences (IES) makes between "confirmatory"…

PCI Education conducted a three-year longitudinal study to determine the comparative effectiveness of the "PCI Reading Program" ("PCI") for students with severe disabilities as implemented in Florida's Brevard Public Schools and Miami-Dade County Public Schools. The primary question addressed by the study is whether students…

PCI Education sought scientifically based evidence on the effectiveness of the "PCI Reading Program--Level One" for students with severe disabilities. During the 2007-2008 academic year. Empirical Education conducted a randomized control trial (RCT) in two Florida districts, Brevard and Miami-Dade County Public Schools. For this…

Under the "Math Science Partnership Grant," the Maui Hawaii Educational Consortium sought scientifically based evidence for the effectiveness of Carnegie Learning's "Cognitive Tutor[R]" (CT) program as part of the adoption process for pre-Algebra program. During the 2006-2007 school year, the researchers conducted a follow-on…