The Michigan Autism Spectrum Questionnaire: A Rating Scale for High-Functioning Autism Spectrum Disorders

Although the DSM-5 has recently created a single category of autism spectrum disorder (ASD), delineation of its putative subtypes remains clinically useful. For this process, screening instruments should ideally be brief, simple, and easily available. The aim of this study is to describe the validity of one such instrument. We administered the Michigan Autism Spectrum Questionnaire (MASQ), a 10-item questionnaire, to 42 patients with ASD (age range 6–13 years, mean 9.7 years, SD 2.5, one female) and 18 patients with other psychiatric disorders (age range 6–17 years, mean 11.7 years, SD 3.8, 6 females). Responses to each item were scored from 0 to 4 yielding a total score of 30. Patients with intellectual disability were excluded. As a group, patients with ASD scored higher than those with other psychiatric disorders (Chi-square test with 1 df = 16.019, ). Within the ASD group, a linear discriminant analysis found that the best cut-off points were 22 or above for Asperger syndrome, 14 to 21 for autism/PDDNOS, and less than 14 for those with other psychiatric disorders. We propose that the MASQ can be used as a brief measure to screen high-functioning ASD from other psychiatric disorders and to identify its possible subtypes. 1. Introduction Autism is a developmental disorder characterized by a distinct pattern of social and communication impairment with rigid ritualistic interests first described by Kanner [1]. It is sometimes divided into high- and low-functioning types depending on the level of intelligence of the affected individual. Almost 40 years after its initial description, it was introduced as infantile autism in the DSM-III [2]. Subsequently, the DSM-III-R [3] introduced the concept of Pervasive Developmental Disorders (PDD) to describe a group of conditions marked by similar deficits of socialization, communication, and imagination, consisting of the main category of autistic disorder and a residual entity of Pervasive Developmental Disorder Not Otherwise Specified (PDDNOS). Reflecting the increasing interest in Asperger Disorder (or Asperger syndrome) [4], the DSM-IV [5] added it to the group of PDD along with Rett’s Disorder and Disintegrative Disorder and retained PDDNOS. However, the recently published DSM-5 has combined autistic disorder, Asperger syndrome, and PDDNOS into a single category of autism spectrum disorder (ASD) and eliminated Rett’s and Disintegrative Disorders [6]. The decision to merge the three disorders was apparently taken because they could not be easily distinguished from each other. However, differentiating Asperger