The Optimal Design Software for Multi-Level and Longitudinal Research includes a series of empirical estimates of plausible parameter values for determining the minimum effect size that can be detected by a given number, size, and treatment/group mix of randomized groups. This information (estimated values of intraclass correlations for groups and R-squares for baseline covariates) is currently available in OD+ for studies that randomize elementary, middle, or high schools to estimate average intervention effects on student reading and math achievement and for studies that randomize preschools or Head Start centers to estimate average intervention effects on social-emotional or cognitive student outcomes. OD+ now provides tabular output (to complement its existing graphical output) that can be printed or saved to document the research design process.
Learn more about this software and contact the developers here.
