عنوان مقاله [English]
Aim: Wechsler’s intelligence scales are among the most common psychological instruments in clinical and research settings used in order to assess intelligence in general and its structure. Given the ambiguity and contradictions regarding its underlying structure, this study is aimed at determining the assumed basic structure of WISC-IV using Multidimensional Scaling, Exploratory Factor Analysis and Confirmatory Factor Analysis. Method: 200 male students studying at 6th distinct of Tehran were sampled using cluster sampling method. Results: Gathered data from individual assessments were analyzed via SPSS-21 and AMOS-18 software. MDS resulted in 3 separate dimensions (processing speed vs. working memory, lexical knowledge vs. visual alertness and perceptual reasoning vs. verbal comprehension). Three components were extracted using Exploratory Factor Analysis including comprehension and perceptual reasoning, working memory and processing speed. Fit indices of Second-Order Confirmatory Factor Analysis along with some modifications confirmed the 3-factorial model derived from previous stages. Conclusion: The results showed that WISC-IV scores could be better understood using 3-factorial solution comparing with the existing 4-factorial structure.