IDENTIFICATION OF FACTOR MODELS FOR THE WISC-III

Confirmatory factor analysis was used to test three models of the WISC -III including Wechsler's original two-factor conceptualization, Kaufm an's three-factor model, and the four-factor model proposed in the WIS C-III manual. Correlation matrixes and standard deviations for the sta ndardization sample for age groups 6 to 16 provided in the WISC-III ma nual were used as input to LISREL 7 to test the three models. Statisti cally, none of the models fit the data very well except for the three- factor and four-factor models for ages 6 and 9. However, incremental f it and cross-validation indexes showed the four-factor model fit the d ata better for all age groups. Because there is no psychological theor y to support the four-factor conceptualization of the new WISC-III, ad ditional theoretical and empirical research is needed to clarify the t hird and fourth factors. Until such research is conducted, these facto rs remain enigmatic and bring into question their usefulness for clini cal and research efforts,