An evaluation of non-verbal tests of intelligence for use with deaf children

Abstract

The effects of prelingual deafness on language development, and its bearing on intelligence are described. The special problems in testing deaf children, and the need to ascertain the suitability of intelligence tests for use with the deaf are explained. Four non-verbal tests of intelligence were selected for evaluation, the Performance Sub-scale of the Wechsler Intelligence Scale for Children, Raven's Coloured Progressive Matrices, the Columbia Mental Maturity Scale and the Goodenough-Harris Drawing Test. Two criteria of educational progress and attainment were devised. The tests were administered to 125 children in a school for the deaf, aged five to twelve years. Tests of pure-tone hearing loss were also applied. Educational progress and attainment were recorded over a period of from four to eight years after the original testing. The test results were examined with regard to reliability, distribution, relationship with WISC (Perf.) (in the case of the three other tests), predictive validity and relationship with hearing loss. It was found that, within this group of deaf children, degree of hearing loss was unrelated to any of the tests. It was concluded that the WISC (Perf.) and the G-HDT were both suitable for use with deaf children over the age range five to twelve years, that the CPM was suitable for use with children aged nine to twelve years, and that the CMMS was not satisfactory for use with deaf children.