What Can the WISC-R Measure?

The WISC-R was investigated by using measures profile (multivariate) reliability in order to determine most reliable dimensions and the precision similarity of the multivariate structure across groups. Due to differences among the 11 age in both subscale reliabilities and true score matrices, it was concluded that the precision measurement differed across age groups. finding was further supported by a comparison canonical reliability coefficients and composites for each age group. However, exhaustive of Varimax rotated profile dimensions that the structure of the WISC-R is rather stable across age groups, but the of that structure differs systematically. A of the analyses indicated that (1) the -R allows highly reliable comparisons of profile (Full-Scale IQ) at each age level; that (2) reliable comparisons of Verbal-Performance can be made at each age level; but (3) for other comparisons, caution should be because of age group differences and potentially unreliability. Two strategies for the of WISC-R profiles, which take into the above findings, are offered.