Clinical validity of the children's category test-level 2 in a mixed sample of school-aged children.

The Children's Category Test (CCT) is a widely used measure of problem solving with adequate psychometric properties. Yet, Shriver and Vacc (n.d.) were fairly critical of the CCT in The Mental Measurement Yearbook and highlighted its limitations. Thus, to explore the clinical validity of the widely used CCT-Level 2 (CCT-2) version, results of that test were analyzed post hoc in a sample of 265 children with mixed etiology referred for neuropsychological testing at a private outpatient laboratory. Overall, the CCT-2 correctly classified 57.7% of the sample, with 72.2% accuracy in classifying the Neuropsychologically Normal Clinical Comparison group but only 54% for the Brain Injured group. Predictive power was further reduced when the Brain Injury group was subdivided. Predictive power fell to 27.2%, with the best predictions coming for the Mental Retardation (MR) group (58.3%) and the lowest for the Learning Disorder NOS group (2.5%). The current findings suggest that the CCT's clinical application should be used with caution.