A convergent validity of wechsler abbreviated scale of intelligence in comparison to wechsler adult intelligence scale
Abstract
Objective: A standard intelligence testing using Wechsler Adult Scale of Intelligence - Third Revision (WAIS-III) is time demanding. Wechsler Abbreviated Scale of Intelligence (WASI) is a standardized tool for a brief intelligence testing and a reliable estimate of intelligence level.
The aim of the current study was to report convergent, discriminative, and predictive validity coefficients of WASI Czech version. Materials and method: A sample of 45 adults (a subsample of university students (US) and MENSA members with > 2 SD intelligence level) and 18 children were included in the present study.
We administered Intelligence Structure Test (I-S-T 2000 R) and Viennese Matrices Test (VMT) to a group of adults, and afterward WASI-WAIS-III in reversed order to suppress the test-retest effect; and WASI - Wechsler Intelligence Scale for Children (WISC-III) in reversed order to the children group. Results: The internal consistency of WASI (four subscales) in adults was poor (stratified Cronbach's α > .6), however, in children was excellent (stratified Cronbach's α > .9).
In adults, WASI total raw score (TRS) correlates with WAIS-III TRS (r = .611), with I-S-T 2000 R TRS (r = .741), and with VMT (r = .362, all p's < .001); in children correlates WASI with WISC-III TRS (r = .917, p < .001). WASI TRS is highly discriminant regarding the differentiation of US and MENSA members (p < .001, η2 = .387).
WASI Verbal and Performance scale explained 39% of total variance in WAIS-III, 56% of I-S-T 2000 R, 28% of VMT, and 84.5% in WISC-III by children. Conclusion: WASI Czech version shows high coefficients of convergent, discriminative, and predictive validity in comparison to highly standardized intelligence tests in children and to a certain degree in adults as well.
WASI seems to be a promising instrument for a brief and reliable intelligence measurement. Study limitation: A modest sample size