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Wechsler Intelligence Scale for Children (WISC) The WISC is an intelligence or IQ test developed in 1949 to measure the intelligence of children ages 5 to 15 years. There have been a number of revisions. There is also a preschool version – the Wechsler Preschool and Primary Stage of Intelligence (WPPSI) – and an adult version – the Wechsler Adult Intelligence Scale (WAIS). This test is made up of 13 subtests organised into two groups, that is Verbal and Performance Scales. It provides three IQ scores: verbal, performance and full-scale IQ. The WISC provides verbal, performance and full-scale deviation IQs based on a mean of 100 and a standard deviation of 15. The WISC has high reliability and predictive validity. Information collected through the test includes information about a child’s strengths and weaknesses in language and performance. This information is arrived at through comparing the verbal score to the Performance score. One of the main uses of the WISC in special education is to compare a child’s ability with their level of achievement in order to identify a specific learning disability. There are various methods and formulae for calculating ability-achievement discrepancies and there are also limitations to ability-achievement discrepancy analysis. These limitations include age range limits and limited exposure to learning experience. Furthermore, severe discrepancy does not necessarily indicate a learning disability. Other evidence is needed to support a diagnosis of a specific learning disability. The disability must not be due to factors such as visual or hearing impairment, mental disability, medical conditions, emotional or behavioural difficulties and educational or socio-economic deprivation. There are controversies regarding the measurement of intelligence and the use of IQ tests. These controversies involve issues concerning bias in test measurement, bias in prediction, test fairness, cultural bias, the heritability of intelligence and the consistency and modifiability of IQ.