WISCIV

The Wechsler Intelligence Scale for Children—Fourth Edition (WISC-IV) is an individually administered intelligence test designed to assess cognitive ability in children. Published in 2003 by The Psychological Corporation (later Harcourt Assessment, now Pearson), it is the fourth edition of the Wechsler scales for children. The WISC-IV is intended for ages 6 years 0 months through 16 years 11 months and is used in educational, clinical, and research settings to estimate general intellectual ability and to profile cognitive strengths and weaknesses.

The WISC-IV yields a Full-Scale IQ (FSIQ) and four primary index scores: Verbal Comprehension (VCI), Perceptual Reasoning (PRI), Working Memory (WMI), and Processing Speed (PSI). Ten core subtests contribute to these scores, with five supplementary subtests available to extend interpretation or compute alternative composites. In addition to the FSIQ and the four indices, the WISC-IV provides two optional composite scores: General Ability Index (GAI), which combines VCI and PRI to estimate general reasoning independent of processing speed and working memory, and Cognitive Proficiency Index (CPI), which combines WMI and PSI to reflect cognitive efficiency. Subtests are administered one-on-one, and results are interpreted using age-normed scores.

Standardization relies on a representative sample, with FSIQ and index scores scaled to a mean of 100 and a standard deviation of 15, and subtest scaled scores with a mean of 10 and SD of 3. Reliability estimates are generally high, including strong test-retest reliability, with validity supported by correlations with other measures of intelligence and achievement, though patterns vary across populations.

The WISC-IV remains in use in some contexts alongside newer editions (notably the WISC-V). It is commonly employed to aid in diagnosing cognitive disorders, identifying learning disabilities, guiding educational planning, and informing clinical decisions, always as part of a comprehensive assessment.