Is the Vineland-3 Comprehensive Interview Form a Multidimensional or Unidimensional Scale? Structural Analysis of Subdomain Scores Across Early Childhood to Adulthood.

As the Vineland Scales are among the most relevant, well-developed, and popular measures of adaptive behavior available for use, this study evaluated the factor structure and dimensionality of the Vineland-3 Comprehensive Interview Form. Drawing data from 2,560 participants in the norming sample, exploratory and confirmatory factor analyses were completed across two independent samples from four age-groups ranging from preschool-age children to adults. Results from exploratory factor analysis revealed evidence for a unidimensional model across age-groups, but results from confirmatory factor analysis indicated that multidimensional models were better fitting than unidimensional models for each age-group. Discussion focuses on whether the Vineland-3 Comprehensive Interview Form is truly a unidimensional or multidimensional measure.