Comparison of McCarthy General Cognitive Indexes and Stanford-Binet IQs for educable mentally retarded children

15 Educable Mentally Retarted children, aged 6 1/2 to 8 1/2 yr., were tested on the McCarthy Scales of Children's abilities and the Stanford-Binet (1972 norms). All children were tested over a 6-mon. period in public schools located in Northeast Georgia. Since 8 of the 15 children obtained General Cognitive Indexes below the norms presented in the McCarthy manual, extrapolated scores were assigned to increase the precision of the comparison. Although the two scores correlated significantly, the mean Index with IQ was significantly lower than the mean IQ for this sample of educable mentally retarded children. The implications of the findings were discussed.