This paper examines the properties of two nonexperimental study designs that can be used in educational evaluation: the comparative interrupted time series (CITS) design and the difference-in-difference (DD) design. The paper looks at the internal validity and precision of these two designs, using the example of the federal Reading First program as implemented in a midwestern state.
This paper presents a conceptual framework for designing and interpreting research on variation in program effects. The framework categorizes the sources of program effect variation and helps researchers integrate the study of variation in program effectiveness and program implementation.
Relying on 427 classroom observations conducted over a three-year period, this study traces changes in teachers’ instructional practices in the First Things First schools.