Stark R E, Tallal P, Kallman C, Mellits E D
J Psychol. 1983 May;114(1st Half):9-19. doi: 10.1080/00223980.1983.9915390.
The performance and verbal IQ scores for the WPPSI and WISC-R were compared for two groups of children aged 5 to 8 1/2 years, one normal and one specifically language delayed (SLD). There 34 to 38 children in each group. In accordance with selection procedures, performance IQ scores were not significantly different across the two groups. Both verbal and full scale IQ were significantly lower for the SLD than for the normal group. Profiles of verbal subtest scores differed for normal and SLD children but profiles for performance subtest scores did not. Variability of performance subtest scores was not greater for the SLD than for the normal children. The results do not support the hypothesis that language delay in children is related to a nonverbal cognitive deficit.
