The numerous acronyms, intelligence tests and assessments can be overwhelming to 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 WISC stands for Wechsler Intelligence Scale for Children. The WISC measures two major aspects of intelligence in children: Verbal and performance intelligence. The verbal intelligence can include things like vocabulary and comprehension. The performance intelligence may include items involving picture completion and reasoning. In general this test is typically used for children 6-16. The exam usually takes about 65-80 minutes to administer. The scores are typically very easy to interpret with 100 being the average score with higher scores indicating higher than average intelligence and vice versa. You may be familiar with the adult version of this assessment, the WAIS (the Wechsler Adult Intelligence Scale)


The WIAT stands of the Wechsler Individual Achievement Test. An achievement test measures how an individual is doing in areas of academic school work. The WIAT give a summary of function in common school subjects like reading, math, written language, and oral language. Similarly to the WISC an average score is 100, above this average indicates above average functioning and below is below average. The age range is broad starting at 4 years to 19 years old.

What is the difference?

These exams 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 you child is falling behind in an academic setting, having them complete these assessment 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 is cause 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 there scores are about even, they may be achieving to their fullest potential, which can allow to your make parenting decisions and provide support accordingly.

It is important to remember that assessments are not facts. There are many factors that can impact the accuracy of an assessment like cultural difference, the environment the assessment is given, 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 behavioral barriers.

If you are interested in learning more about educational assessments for children or would like to sit down and talk to a child psychologist about your concerns book in a time to speak to a psychologist call us on (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