IMPLICATIONS OF THE TRUE SCORE MODEL IN ASSESSMENT OF MOOD STATE

Several investigators have used the Profile of Mood States (POMS) to a ssess general mood states. In these studies, POMS scores have been use d as pre- and post-intervention assessments, with changes in mood stat es being attributed to the intervening factor. We propose that such us e may be inappropriate relative to true score theory, particularly in the absence of adequate control groups. To demonstrate that single-adm inistration assessments of current mood states cannot be considered in dicative of stable mood patterns, we compared single-administration sc ores to average mood state measures derived from 18 separate assessmen ts collected over three days. Results suggested that single-assessment values are significantly different from multiple-assessment averages and that the standard error of the measure is such that single-adminis tration scores cannot be confidently interpreted.