Date of Graduation

Spring 2021


Master of Science in Applied Behavior Analysis



Committee Chair

Jordan Belisle


Content validity describes the degree of which a measure represents all the components of the overall construct being measured. Behavior analytic language assessments are largely based on Skinner’s verbal operant theory (1957). Three behavior analytic language assessments were utilized to measure the coverage of Skinner’s verbal behavior theory: the VB-MAPP, ABLLS-R, and PEAK. The purpose of the current study was to examine the content validity of each of these assessments coverage on the totality of Skinner’s verbal operant theory. Expressive items on each of the three assessments were compared to definitions of Skinner’s verbal operants and were coded as the corresponding verbal operant. The results of this analysis indicated that all three assessments used all of the primary verbal operants, however PEAK utilized the largest number of the extended versions of the verbal operants. The assessment that utilized the lowest number of extended verbal operants was the VB-MAPP. The results of this study indicated that the top three assessments utilized by behavior analysts cover less than 25% of the totality of Skinner’s verbal operant theory. Implications of this study demonstrate the lack of coverage on all of Skinner’s verbal operants, and further proposes that the complexity of language may not be accounted for in totality by Skinner’s theory; future research should be conducted using newer accounts of language learning such as relational frame theory to provide a more robust account of human language learning.


ABLLS-R, autism spectrum disorder, language, language assessment, PEAK, VB-MAPP, verbal behavior, verbal operants

Subject Categories

Applied Behavior Analysis | Behavioral Disciplines and Activities | Behavior and Behavior Mechanisms | Communication Sciences and Disorders | Disability Studies | Linguistics | Special Education and Teaching


© Taylor Marie Lauer

Open Access