Optimal refinement of the rating scale

Abstract

Ratings of parent behavior were obtained by means of a graphic rating scale. The scale was divided into various numbers of units, and the score of each subject was computed using each scale. As the number of intervals was increased up to about 12 reliability increased markedly. A less marked increase was manifested up to about 30 intervals, beyond which point there was a slight decrease. This curve does not correspond to that expected on the basis of Symonds' function for the optimal number of scale divisions. (PsycInfo Database Record (c) 2025 APA, all rights reserved)