Multisite trials, in which individuals are randomly assigned to alternative treatment arms within sites, offer an excellent opportunity to estimate the cross-site average effect of treatment assignment (intent to treat or ITT) "and" the amount by which this impact varies across sites. Although both of these statistics are substantively…

Researchers sometimes need a statistical test of the hypothesis that two values of Cronbach's alpha reliability coefficient are equal. The situation may involve scores from two different measures administered to independent random samples or from the same measure administered to random samples from two different populations. Feldt derived a test…