Standard intelligence tests , such as the Stanford-Binet , are often inappropriate for children with autism and dyslexia ; the alternative of using developmental or adaptive skills measures are relatively poor measures of intelligence in autistic children , and have resulted in incorrect claims that a majority of children with autism are mentally retarded . Standard intelligence tests , such as the Stanford-Binet , are often inappropriate for children with autism ; the alternative of using developmental or adaptive skills measures are relatively poor measures of intelligence in autistic children , and may have resulted in incorrect claims that a majority of children with autism are mentally retarded .