Beyond these design and execution issues, the worthiness of an
educational intervention study is also reflected by both the significance
of its research contribution to the field and its impact on
educational practice, with the latter reflecting Levin’s (1994)
“creditability” characteristic. In addition, nonexperimental research
methods (e.g., surveys, interviews, observations) can be
helpful when used to describe parameters (e.g., components, implementation)
and consequences (both intended and unintended) of
an intervention when disseminating information about the intervention
to educators. Future studies of the quality of intervention
research should examine these characteristics, the internal validity
aspects mentioned above, and others. For example, what are the
costs in terms of time, money, training, and so forth of the
intervention vis-a`-vis its expected payoffs? No matter how “creditable”
an intervention may be, if the cost– benefit ratio is too
high—or even if the absolute costs associated with the intervention
are exorbitant—then the intervention becomes simply an
interesting idea that is impractical to implement. We encourage
researchers to explore questions and issues such as these, with the
hope that eventually educational intervention research will increase
in both its quantity and quality.