Methodological problems in the retrospective computation of responsiveness to change: The lesson of Cronbach

OBJECTIVE: To examine the relation between responsiveness coefficients derived directly from a calculation of average change resulting from a treatment intervention (Responsiveness-Treatment or RT) and those derived from retrospective analysis of changed and unchanged groups (Responsiveness Retrospective or RR) based on a global measure of change. METHOD: Two approaches were used. First, we used simulation methods to examine the analytical …