Purpose of the Questionnaire (Scale)

The GAMA is designed to provide a brief, culturally neutral assessment of adults’ general intelligence, to evaluate nonverbal cognitive abilities in populations with cultural diversity, as well as to support clinical and professional assessments. It is used by psychologists, researchers, and career counselors.

Questionnaire (Scale) Analysis

The instrument was developed by Naglieri, J.A. and Bardos, A.N. in 1997 and includes XX items with visual patterns. It consists of four domains: Relations (XX items), Analogies (XX items), Mental Synthesis (XX items), and Detail Recognition (XX items).

Scoring of Items

Scoring is binary (0–1), with 1 point awarded for each correct answer. Each subscale yields standardized scores with a mean of 10 and a standard deviation of 3, while the total score is converted into an Intelligence Quotient (IQ) (Mean = 100, Standard Deviation = 15). Administration can be done individually or in groups and lasts 20–30 minutes.

Statistical Analysis

The standardization of the instrument was conducted on a sample of 2,360 adults from the United States, aged 18–96 years. Score interpretation is as follows: 70–84 indicates below average level, 85–115 average level, and 116–130 above average level. For example, an IQ of 120 indicates high ability in nonverbal reasoning.

Validity of the Questionnaire (Scale)

Construct validity is supported by significant correlations with the WAIS (r = 0.75) and KBIT (r = 0.72). Cultural neutrality is reinforced by minimal bias across ethnic and linguistic groups. It is based on studies such as the original validation by Naglieri & Bardos (1997) and a pilot Greek study with a sample of 99 individuals, which showed similar results to the original standardization.

Reliability of the Questionnaire (Scale)

Overall internal consistency is high (Cronbach’s α = 0.90). Reliability varies across age groups, with 0.94 for individuals aged 35–44 years and 0.79 for individuals aged 80–96 years. Detailed data are presented in the Technical Manual by Naglieri & Bardos (1997).

References

Naglieri, J.A. & Bardos, A.N. (1997). General Ability Measure for Adults. NCS Assessments.

Keywords

Nonverbal intelligence index, adult assessment, cognitive abilities test, cultural neutrality, psychometrics