WISC-III Third Factor: Critical Measurement Issues

Abstract

Content validity of the Third Factor of the Wechsler Intelligence Scale for Childre-n-Third Edition (WISC-III) was evaluated by asking undergraduates to label the factor represented by items like those on the Arithmetic and Digit Span subtests. Participants unfamiliar with the content of the two subtests choose labels that corresponded with terminology associated with problem solving, memory, and quantitative skills. The concurrent validity of the Third Factor with behavioral measures of attention, hyperactivity, and learning problems was assessed in a sample comprising consecutive referrals to a university-based psychoeducational clinic. There was a moderate relationship between Freedom From Distractibility (FFD) and teacher ratings of learning problems on the Behavior Assessment System for Children-Teacher Rating Scales. There were no significant correlations to suggest concurrent validity between the Third Factor and behavioral ratings of attention problems and hyperactivity. Theoretical and practical implications of the FFD factor are discussed.