Estimates of autism spectrum disorder prevalence may drop under recently revised diagnostic criteria in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition published by the American Psychiatric Association in 2013, according to a study.
DSM-5 criteria differ from the older DSM-IV-TR (fourth edition, text revision) criteria in several ways, including by not distinguishing subtypes of ASD (such as autistic and Asperger disorders); recognizing only two domains of impairment social communication and restricted, repetitive patterns of behavior, interests or activities; and requiring all three items in the social communication domain.
Also, the DSM-5 specifies seven diagnostic criteria but some describe more general principles and behaviors than in DSM-IV-TR, and the DSM-5 criteria allow historical behaviors to be considered in addition to current behaviors, researchers noted in background information for the study, which was published Jan. 22 on the website of JAMA Psychiatry.
Matthew J. Maenner, PhD, of the National Center on Birth Defects and Developmental Disabilities at the CDC in Atlanta, and colleagues evaluated the potential effects of the new criteria for diagnosing ASD by applying them to 8-year-olds who are part of a large ASD surveillance system in the U.S.
Among 6,577 children classified as having ASD based on DSM-IV-TR criteria, 81% (5,339) met the DSM-5 criteria for ASD. Using the DSM-5 criteria, ASD prevalence in 2008 would have been 10 per 1,000 people, compared with the reported prevalence of 11.3 based on DSM-IV-TR criteria, according to the study results.
Autism spectrum disorder prevalence estimates will likely be lower under DSM-5 than under DSM-IV-TR diagnostic criteria, although this effect could be tempered by future adaptation of diagnostic practices and documentation of behaviors to fit the new criteria, the authors wrote.
Study abstract: http://archpsyc.jamanetwork.com/article.aspx?articleid=1814891