THE FACTOR STRUCTURE OF THE WECHSLER-ADULT-INTELLIGENCE-SCALE-REVISED- ONE OR 2 BUT NOT 3 FACTORS

One-, 2-, and 3-factor solutions for the WAIS-R normative samples were examined using principal components analysis with varimax rotations. Factors were examined across age groups by computing congruence coeffi cients and root mean square differences to determine the equivalence a nd consistency of factors across age groups. There is strong evidence for the general (g) and 2-factor (verbal and perceptual organization) solutions but noticeably less support for memory/freedom from distract ibility in the three-factor solution. Verbal and perceptual organizati on factors were also attenuated in the three-factor solution. One and 2-factor solutions were essentially equally justifiable but because th e 1-factor solution was weighted most heavily with verbal measures, th e 2-factor solution may be advantageous because this solution does dis tinguish between verbal and performance measures. (C) 1998 John Wiley & Sons, Inc.