Increased Power Through Design and Analysis

This study was suggested by the frequent encounters of the authors with beginning researchers who tend to avoid the more powerful research designs and statistical procedures such as the Solomon Four-Group design and analysis of covariance. The combination of an effective design and a powerful statistical analysis technique resulted in a significant finding for only 44 learning disabled students. Researchers are encouraged to seek pre-existing or easily obtainable covariates to incorporate into the statistical treatment whenever added power is required.