The Wechsler Intelligence Scale for Children Essay

The Wechsler Intelligence Scale for Children - Essay Example The WISC-III was standardized on a representative sample in North America based on U.S.A. census data for 1988 (N = 2,200) (Canivez, Neitzel, & Martin, 2005). The sample was stratified across age, gender, ethnicity, geographical region, parental occupation, and urban-rural residency (Kaplan & Saccuzzo, 2001). A four-factor model of index score is widely supported (i.e., Verbal Comprehension, Perceptual Organization, Freedom from Distractibility, and Processing Speed) (Canivez, Neitzel, & Martin, 2005). The WISC-III has high internal consistency for all three IQ scores and the four factors, ranging from .80 to .97 (Canivez, Neitzel, & Martin, 2005; Kaplan & Saccuzzo, 2001). This reflects the 11 subtests (Symbol Search and Coding excluded) reported moderate to excellent internal consistencies, of .61 to .92 (Kaplan & Saccuzzo, 2001). Split-half reliabilities for the three IQs in 1991 were found to be .96 (FSIQ), .95 (VIQ), and .91 (PIQ) (Kaplan & Saccuzzo, 2001). Standard errors of measurement for FISQ, VIQ and PIQ average at 3.20, 3.53, and 4.54 respectively (Kaplan & Saccuzzo, 2001).