repeated contrast
in a within-subjects analysis of variance, a comparison of means conducted across different levels of the independent variable. For example, assume a researcher is interested in how commitment to therapy changes over the course of the process. He or she could assess participant commitment at the start of therapy (Month 1) and at the beginning of each of the four months thereafter, and then evaluate how the mean commitment scores at Months 2, 3, 4, and 5 differ from the mean baseline commitment score obtained at Month 1. There are several types of repeated contrasts available, such as simple comparisons and polynomial contrasts.