Prevalence of low scores in children and adolescents on the test of verbal conceptualization and fluency.

It is important to consider the prevalence of low scores when administering a battery of psychological tests. Understanding the prevalence of low scores is important for minimizing false-positive diagnoses of cognitive deficits in clinical practice. The purpose of this study was to expand the literature on base rates for use in children and adolescents. Participants were 408 healthy children and adolescents (M(age) = 13.1 years, SD = 3.7) and 139 children and adolescents (M(age) = 12.4 years, SD = 3.1) diagnosed with a medical, neurological, or learning condition. All participants were administered the Test of Verbal Conceptualization and Fluency (TVCF; Reynolds & Horton, 2006 ). The clinical sample performed significantly lower compared with the healthy control participants on three of the five TVCF scores. When all scores were considered simultaneously, 38% of healthy children obtained one or more scores below the 16th percentile and 15% had one or more scores in the 5th percentile or lower. By comparison, significantly higher proportions of children in the clinical sample had low scores below each of the five cutoffs (i.e., 63% had one or more test scores below the 16th percentile and 37% had one or more scores in the 5th percentile or lower). Our findings illustrate the importance of considering the prevalence of low TVCF scores in everyday clinical practice with children and adolescents.