| Roundtable: Returning to the Causal Explanatory Tradition: Lessons for Increasing the External Validity of Results From Randomized Trials |
| Roundtable Presentation 615 to be held in Balboa A on Friday, Nov 4, 10:45 AM to 11:30 AM |
| Sponsored by the Theories of Evaluation TIG |
| Presenter(s): |
| Denis Newman, Empirical Education Inc, dn@empiricaleducation.com |
| Andrew Jaciw, Empirical Education Inc, ajaciw@empiricaleducation.com |
| Abstract: Program evaluation in education falls into two main traditions: the causal explanatory school represented by Lee Cronbach and associates, and the school based on activity theory for which the randomized trial is the gold standard method. The former prioritizes external validity, the latter, internal validity. We posit that the divide between them is unnecessary and we examine how the causal explanatory tradition can inform the planning, conduct and analysis of randomized trials to increase external validity of findings. The result is a set of guiding principles that stress the importance of articulating the theory of the mechanism of treatment-in-context, selecting different contexts to allow for treatment heterogeneity, building context-by-treatment interactions into the analysis, and corroborating (or rejecting) and advancing further theory concerning the intervention in context. Combined, these principals support a program by which randomized trials of an intervention progressively establish external validity. |