WASI-II Wechsler Abbreviated Scale of Intelligence

The WASI-II (Wechsler Abbreviated Scale of Intelligence) is an IQ test for ages 6-90.  It is a shorter and simpler measure based on the more comprehensive Wechsler Intelligence Scale for Children (WISC) and the Wechsler Adult Intelligence Scale (WAIS). 

WASI-II measures cognitive abilities across a range of domains and provides an estimate of a person's general intellectual ability (or Full Scale IQ - FSIQ). It is often used in research studies, and often used to screen for intellectual disability or giftedness, or to assess cognitive abilities in the context of neuropsychological evaluations or clinical diagnoses.

Uses in autistic population

• Assessment of Cognitive Abilities: believed to help identify cognitive strengths and weaknesses in verbal comprehension and perceptual reasoning, which can be informative for planning educational/ behavioral interventions.
• Research: frequently used in autism research studies as measure of cognitive ability.
• Diagnosis: While the WASI-II itself isn't a dx tool for autism, it can be part of a broader diagnostic assessment as it is believed that understanding an individual's cognitive functioning can perhaps provide context for other symptoms or behaviors.

IQ Testing

IQ is a measure designed to assess an individual's cognitive abilities and intellectual functioning; specifically it aims to assess various aspects of intelligence, including verbal comprehension, perceptual reasoning, working memory, processing speed, and problem-solving abilities. These tests typically cover domains such as language, math, spatial reasoning, and logical thinking.

IQ scores are derived by comparing an individual's performance on the test to a representative sample of the population. The scores are standardized and follow a bell curve distribution, with the average score set at 100. Scores above 100 indicate above-average intelligence, while scores below 100 indicate below-average intelligence. The standard deviation is typically 15 points, meaning that about 68% of the population falls within the range of 85-115.

Commonly used IQ tests in Autism 

• WAIS: Wechsler Adult Intelligence Scale (ages 16-90)
• WISC-V: Wechsler Intelligence Scale for Children (ages 6-16)
• KABC-II: Kaufman Assessment Battery for Children (ages 3-18)
• MSEL: The Mullen Scales of Early Learning (ages birth - 5)
• DAS: The Differential Ability Scales (ages 2-17)
• Leiter-R (ages 2-20+)
• RIAS (ages 3-94)
• CAS Cognitive Assessment System (ages 5-17)

See Post: Why is IQ Testing especially problematic in the Autistic Population

Other general problems and limitations of IQ Testing:

• Narrow Assessment: IQ tests primarily measure cognitive abilities related to academic success and may not capture the full range of human intelligence, such as creativity, emotional intelligence, or practical skills.
• Cultural Bias: IQ tests have been criticized for potential cultural bias, as they may reflect the experiences, values, and knowledge of specific cultural or socioeconomic groups. Some questions or tasks may be more familiar or relevant to individuals from certain backgrounds, leading to potential disparities in scores.
• Limited Contextualization: IQ tests provide a snapshot of an individual's abilities at a specific point in time and may not account for the influence of environmental or socio-economic factors, educational opportunities, or individual motivation on test performance.
• Interpretation Challenges: IQ scores are often misinterpreted or used as a sole indicator of an individual's worth or potential, neglecting the complexity of human intelligence and the importance of other factors such as motivation, personality traits, or social and emotional skills.

History: The concept of IQ testing dates back to the early 20th century. Alfred Binet and Theodore Simon developed the first modern intelligence test in 1905. Over time, numerous IQ tests have been developed, revised, and standardized.