Impairments in social communication are the core diagnostic features of autism spectrum disorders (ASD). In the past two decades findings from important clinical research studies have translated into improvements in understanding and practice, for example leading to a reduction in the age at which autism is commonly first recognised and diagnosed…

Reviews a recent paper by Levy (1982) which concluded that a new format of the Peabody Picture Vocabulary Test was valid for autistic children. Claims the analysis was inappropriate and presents a statistical test to compare differences between independent mean differences. Includes a reply by Stine Levy. (Author/JAC)