CRYSTALLIZED INTELLIGENCE AND WISC-R

Based on the results of the 1 066 children, of 6 to 16 years of age, who participated in the French standardization of the WISC-R, and using an actuarial method (stepwise multiple regression), we evaluated the relative impact of certain socio-demographic determinants in the development of crystallized intelligence (measured by a multifactorial scale). The evolution of the percentage of variance explained in the determination of global intellectual efficiency, is roughly linear from the age of 6 to 16. This percentage is very low at the age of six, 8%, and rises to 54% at the age of 14. The second finding centers on the differential aspect of prediction between the verbal scale and the performance scale. Prediction is considerably better for socialized and intentional learning (verbal scale) and a lot weaker (although increasing with subject age) for incidental learning which has little sensitivity to environmental characteristics.