The study by Canivez et al. (2009) aimed to investigate the construct validity of two abbreviated measures of intelligence: the Wechsler Abbreviated Scale of Intelligence (WASI) and the Wide-Scale Intelligence Test (WRIT). The research, conducted with a sample of 152 children, adolescents and adults, sought to verify whether the internal structure of these tests reflected the theoretical model of intelligence that underpinned their construction.
The authors used exploratory and confirmatory factor analyses to examine the latent structure of the WASI and WRIT subtests. The results indicated that both tests showed strong evidence of convergent validity, with high correlations between similar subtests and between the total IQ scores of each test. Exploratory factor analysis revealed a bifactor structure, with one factor representing verbal-crystallized abilities and another representing nonverbal-fluid-visual abilities. However, the high correlation between these two factors suggested the presence of a higher-order factor, general intelligence (g), consistent with hierarchical models of intelligence.
Confirmatory factor analysis corroborated these findings, indicating that a bifactor model with a general intelligence factor fit the data better than a unifactor model. Most of the variance explained by the tests was attributed to the general intelligence factor, with minor contributions from the first-order factors.
The authors conclude that the WASI and WRIT are valid and reliable measures of general intelligence, with an internal structure consistent with hierarchical theoretical models of intelligence. However, the strong influence of the ‘g’ factor suggests that interpretation of the results should focus primarily on total IQ scores rather than on specific factor scores. The study highlights the importance of considering the hierarchical structure of intelligence when interpreting cognitive test results, especially in abbreviated measures.
Reference:
Canivez, G.L., Konold, T.R., Collins, J.M., & Wilson, G. (2009). Construct validity of the Wechsler Abbreviated Scale of Intelligence and Wide Range Intelligence Test: Convergent and structural validity. School Psychology Quarterly, 24(4), 252–265. https://doi.org/10.1037/a0018030
Dr. Fabiano de Abreu Agrela Rodrigues MRSB holds a post-PhD in Neuroscience and is an elected member of Sigma Xi – The Scientific Research Honor Society (more than 200 members of Sigma Xi have received the Nobel Prize), as well as being a member of the Society for Neuroscience in the United States, the Royal Society of Biology and The Royal Society of Medicine in the United Kingdom, the European Society of Human Genetics in Vienna, Austria, and the APA – American Philosophical Association in the United States. He holds a Master’s degree in Psychology and a Bachelor’s degree in History and Biology. He is also a Technologist in Anthropology and Philosophy, with several national and international degrees in Neuroscience and Neuropsychology. Dr. Fabiano is a member of prestigious high IQ societies, including Mensa International, Intertel, ISPE High IQ Society, Triple Nine Society, ISI-Society, and HELLIQ Society High IQ. He is the author of more than 300 scientific studies and 30 books. He is currently a visiting professor at PUCRS in Brazil, UNIFRANZ in Bolivia and Santander in Mexico. He also serves as Director of CPAH – Centro de Pesquisa e Análises Heráclito and is the creator of the GIP project, which estimates IQ through the analysis of genetic intelligence. Dr. Fabiano is also a registered journalist, having his name included in the book of records for achieving four records, one of which is for being the greatest creator of characters in the history of the press.