Intelligence tests have often been used to differentiate "high functioning" from "low functioning" individuals with autism. But a recent study published in the journal Psychological Science suggests that "low functioning" children with autism may in fact score much higher if an alternative intelligence test–the Raven's Progressive Matrices– is used instead of the more conventional Wechsler Intelligence Scale for Children (WISC). This test (see image on left for sample item) assesses abstract reasoning. The scores on the Raven's were on average 30% higher, and in some cases more than 70% higher than their scores on the WISC. The Raven's Progressive Matrices is considered the most complex single test of intelligence in the scientific literature. These new findings suggest that many autistic children who have thus far been labeled "mentally retarded," may now be considered of average or above average intelligence, and thus be seen in terms of their strengths as well as their difficulties.