The mental growth patterns of 204 children were investigated on four different test occasions covering a five-year period, ages six to 11. There is no evidence of intellectual differentiation after age six nor is there a systematic decline in size of WISC subtest intercorrelations with increasing age. (Authors)

The rod and frame performance of 70 children, 5 to 7 years of age, with respect to sex and age differences, reliability, and its relationship to general intelligence, was investigated. The rod and frame test was administered individually and again following a period of 35 to 69 days, at which time the Lorge Thorndike Intelligence Test, form 1A,…