Retarded to Wechsler Subtest Patterns of Mentally Groups: Relationship to g and Estimates of Heritability

From a survey of published data on the Wechsler subtest performance of primarily mild and borderline mentally retarded persons, 4304 protocols from 4004 individuals were collated and their subtest patterns on the WAIS, WAIS-R, WISC, and WISC-R were compared. Rank order correlations of subtest scores on the different scales were statistically reliable for all but the WAIS/WAIS-R comparison. On all but the WAIS, reliable inverse relationships were found between subtest performance and the subtests' g-loadings, indicating that mildly retarded groups tend to score relatively lower on subtests that are better measures of general intelligence. Likewise, reliable and marginally reliable inverse relationships were found between subtest patterns of retarded groups and the subtests' estimated indexes of heritability, raising the possibility that inherited capacities differentially influence the pattern of performance of these groups.