One of the most important factors affecting the use of evidence for policy or practice is the uncertainty of study results. Furthermore, this uncertainty is compounded by our increasing awareness of heterogeneous treatment effects. Here we inform debate about the strength of study evidence by quantifying the conditions necessary to nullify an…

The present study seeks to evaluate a hybrid model of identification that incorporates response to instruction and intervention (RTI) as one of the key symptoms of reading disability. The 1-year stability of alternative operational definitions of reading disability was examined in a large-scale sample of students who were followed longitudinally…