The general ability measure for adults underrepresents true IQ in a high-functioning aviation population

Area of Science:

• Neuropsychology
• Cognitive Assessment
• Psychometrics

Background:

• The General Ability Measure for Adults (GAMA) is a brief, nonverbal assessment of general intellectual ability.
• Research on GAMA's utility in high-functioning populations is limited.
• Cognitive intactness is crucial for accurate intellectual assessment.

Purpose of the Study:

• To evaluate the General Ability Measure for Adults (GAMA) in a high-functioning population.
• To compare GAMA's intellectual ability scores and classifications against the Wechsler Adult Intelligence Scale - 4th edition (WAIS-IV).
• To determine the appropriateness of IQ screeners for individuals with suspected high premorbid functioning.

Main Methods:

• A sample of 59 cognitively intact aviation pilots underwent neuropsychological evaluation.
• Participants were administered both the GAMA and the WAIS-IV.
• Paired samples t-test and Fisher's exact test were used for statistical analysis.

Main Results:

• GAMA yielded significantly lower IQ scores than WAIS-IV (mean difference of 7.54 IQ points).
• Significant disagreement in score classification was observed between GAMA and WAIS-IV.
• Individuals classified as Above Average on WAIS-IV were often classified as Average on GAMA.

Conclusions:

• The GAMA may significantly underrepresent true IQ in both score and classification for high-functioning individuals.
• IQ screeners like GAMA might be inappropriate for assessing individuals with suspected high premorbid functioning.
• Further research is needed to assess the validity of verbal-based IQ screening measures in similar populations.