Comparative three-factor solutions of the WISC-III and WISR-R at 11 age levels between 6-1/2 and 16-1/2 years.

The Wechsler Intelligence Scale for Children, Third Edition (WISC-III) was factor analyzed at ages 6 12 through 16 12 years of age (n = 200 per age group). The study replicated analyses conducted by Kaufman (1975) with the WISC-R using comparable subtests across the two scales. As in the WISC-R study, a three-factor structure emerged as consistent across the age range of the WISC-III: Verbal Comprehension, Perceptual Organization, and Freedom from Distractibility. The results of the study are discussed in terms of their clinical utility with useful statistics for the interpretation of the WISC-III presented.