American Psychological Association, Inc. Issues in Using Quantitative Rating Scales in Developmental Research

Theoretical and practical issues in the use of quantitative judgments in developmental research are reviewed. Judgment is conceptualized as consisting of three components: information valuation, information integration, and translation of impressions into overt responses. It is important to distinguish between developmental changes that occur in different components of the judgment process. Most developmental studies have assumed that rating scales are used in an equal-interval manner, with few attempts to test that assumption. The conditions allowing a conclusion that in-dividuals or groups differ in information integration are outlined, and methods of testing models of the information integration process that do not assume an equal-interval response scale are reviewed. Although these methods require more com-plicated experimental designs, their benefits in identifying the possible loci of de-velopmental changes in judgments outweigh their inconvenience. Development can be characterized as in-volving change in the organization and modes of using information. Modem developmenta