EFFECTS OF AFFECTIVE-SEMANTIC MODE OF ITEM PRESENTATION IN BALANCED SELF-REPORT SCALES - BIASED CONSTRUCT-VALIDITY OF THE ZUNG SELF-RATING DEPRESSION SCALE

The widely applied procedure of balancing self-report instruments by i ncluding positively and negatively keyed items is exemplified by the Z ung Self-rating Depression Scale (SDS). Investigation of the influence of the symptom-positive and symptom-negative item modes on the SDS in a depressed population resulted in two major findings. First, the rev ersed scoring of the symptom-negative items resulted in higher mean it em scores. Secondly, factor analyses of the SDS in the present study a nd in previous research revealed that the semantic modes of item prese ntation were represented in the factor structure of the SDS. These fin dings were confirmed by analyses with the State-Trait Anxiety Inventor y (STAI) and by previous factor analytical research with balanced inst ruments and were interpreted within the framework of the theory of Pos itive and Negative Affect. The present data cast doubts on the constru ct validity of the SDS as a measure of depressive symptomatology due t o the presence of the negatively keyed items and suggest reconsiderati on of the use of balanced instruments for minimization of the acquiesc ence response set.