Statistical Power Analysis and Experimental Field Research

This article discusses the application of statistical power analysis to field experiments in which subjects "trickle-in" through a case-flow process. Statistical power is shown to be useful m guiding research decisions concerning problems often encountered with case-flow designs. Concrete examples drawn from the National Evaluation of Juvenile Restitution Initiative illustrate the utility of power analysis for field experiments m which subjects become available for observation by the flow of clients into an agency or program.