摘要: Abstract Pretest-posttest designs serve as building blocks for other more complicated repeated-measures designs. In settings where subjects are independent and errors follow a bivariate normal distribution, data analysis may consist of univariate or an covariance. Another possible approach is to use seemingly unrelated regression (SUR). The purpose this article help guide the statistician toward appropriate choice. Assumptions, estimates, test statistics each approached in systematic manner. On basis these results, crucial choice whether differences pretest group means conceived be real result pure measurement error. Direct consultation with subject-matter person important making right If real, then recommended. o...