Convergent and Discriminant Validation of Two Methods of Assessing Three Academic Traits

Abstract

A refined and extended analysis of variance (ANOVA) approach was used to investigate the pattern of relationships among arithmetic ability, reading ability, and general ability as assessed by teacher ratings and standardized tests. The subjects were 54 educable mentally retarded children who were rated and tested annually for 3 years. The tests proved to have much higher convergent and discriminant validity than the ratings, and to be much less affected by method bias. These differences are seen as reflecting the natural superiority of standardized tests over teacher ratings for most purposes.