What Is The Difference Between The WISC And The WIAT?

WISC vs WIAT; the numerous acronyms, intelligence tests and assessments can be overwhelming for a parent.  Let’s break down two common intelligence tests typically administered to children and what they are actually measuring.  Both of these test are often used when referring to a child’s IQ, so what are the differences and how are they helpful?


The Wechsler Intelligence Scale for Children (WISC) is a widely used assessment tool that measures various aspects of a child’s cognitive abilities.  It is designed for children between the ages of 6 and 16 years old.  The WISC evaluates a child’s intelligence across several key areas, including verbal comprehension, visual-spatial skills, fluid reasoning, working memory, and processing speed. These different factors are measured through a series of subtests, such as vocabulary, arithmetic, coding, and picture completion.

By assessing a child’s performance on these subtests, the WISC provides an overall intelligence quotient (IQ) score, as well as individual scores for the different cognitive domains. This information can be valuable for identifying a child’s strengths and weaknesses, and for detecting any potential learning disabilities or developmental delays.


The Wechsler Individual Achievement Test (WIAT) is a comprehensive assessment tool used to evaluate a person’s academic skills and knowledge. It is designed for individuals ranging from preschool to adult age.  The WIAT measures performance across several academic domains, including reading, writing, mathematics, and oral language.  It provides standardised scores that can be used to identify strengths, weaknesses, and any potential learning difficulties.

What is the difference?

These assessments on the surface may appear to be very similar, but there is a key difference. The WISC is designed to assess intelligence, not school performance. The WIAT is designed to assess academic performance and does not predict intelligence. It can be useful to compare these scores to see if your child is performing academically up to their intelligence.  It can also highlight areas in school where your child may need more support.  For example if your child is not performing to standard in an academic setting, having them complete these assessments may give you some insight. If their WIAT score is below average and their WISC score is well above average, this may indicate other barriers in an academic setting that may be contributing to the academic set back. Begin to look at other external factors like bullying, home support, motivation, friends, rapport with the teacher, and engagement that may be impacting school performance.  If the scores are about even, they may be achieving to their fullest potential, which can allow you to make parenting decisions and provide support accordingly.

It is important to remember that assessment results must be interpreted with caution.  There are many factors that can impact the accuracy of an assessment like cultural difference, the environment in which the assessment is undertaken, the mindset of the child.  Assessments are designed to be tools and should never be the single determining factor in a major decision.  Assessments can be helpful in identifying learning disorders and ruling out behavioural barriers.

If you are interested in learning more about educational assessments for children or would like to talk to a child psychologist about your concerns, contact us (02) 6262 6157 or book an appointment online.

Related reading:

Creative Ways to Help Children with Learning Disorders
Parenting Strategies to Manage Children with ADHD
Understanding Nonverbal Learning Disorder

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