IQ = M. A. / C. A. x 100 This formula enables us to compare the intellectual levels of different individuals.
Different sets of tests are prepared for different age groups. The choice of a particular test depends upon the age of the subject and the purpose of the test. Some of the commonly used tests to measure children’s intelligence according to age-groups are as follows:
(i) Intelligence scales for infants (0 to 19 months):
In this test the measurement of intelligence depends on the observation of sensory motor activity. The Development schedule prepared by Gessel is the first of its kind for the measurement of infants’ intelligence. It is related to different developmental areas such as motor behaviour, adaptive behaviour (e.
g. eye-hand co-ordination, exploration, and manipulation of objects, etc.) language behaviour (facial expressions, gestures, vocalisation, comprehension, responsiveness, etc.). It is to be noted that these responses are measured in terms of IQ and the results may not match with the IQ tests in the later age.
(ii) Intelligence tests for pre-school children (1 to 3 1/2 years):
The tests commonly used for this age-group are Mevrill-Palmer Scale and Vineland Social Maturity Scale. Children of preschool age are distractible (they cannot concentrate), shy, and unco-operative, therefore, the application of these tests becomes more difficult. The functions showing high productive value are: (1) controlled attention, (2) memory (3) reasoning (4) perceptual relationships. But the tasks involving verbal instructions and motor-co-ordinations show low predictive value. Therefore, the scales give us only approximate idea about the child’s intellectual abilities.
(iii) Intelligence scales for school age children (4 to 16 years):
School age is the period when intelligence tests are widely applied and their results are more reliable.
These tests are used in schools and child guidance clinics. They are useful for diagnosis of mental deficiency, for guiding mentally superior children in their academic courses and for assessing the intellectual levels of maladjusted and delinquent children. Among the various scales Wechsler intelligence Scale is most commonly used. In India Dr. Kamat and Dr. Shukla have constructed intelligence scales suitable for Indian children. All these scales are general scales. They are mainly based on verbal responses of the child.
The major items on these scales include linguistic abilities, number ability, conceptual ability and perceptual ability, etc.
(iv) Non-Verbal or Performance tests:
These tests are more suitable for younger children who cannot verbalise their correct responses (because they have not yet mastered the language to answer the questions). These tests consist of certain actual performance other than verbal responses. On the basis of performances in these tests it is possible to guess the intellectual abilities of the subjects. Some of the commonly used performance tests are Koh’s Blocks.
Draw-a-man test, Form board test. Bhatia’s Scale, etc. There are certain special performance tests for testing intelligence of disabled or handicapped children such as those for blind and deaf children. In all performance tests, minimum use of language is made.