ICD The World Health Organization's International Classification of Diseases (11th Revision) ICD-11, regarded as the global standard, was released in June 2018 and came into full effect from January 2022. It describes ASD thus: ICD-11 was produced by professionals from 55 countries out of the 90 countries involved and is the most widely used reference worldwide. Clinicians use the ICD as a reference for diagnosis and reporting but researchers, particularly in the US, continue to use the Diagnostic and Statistical Manual of Mental Disorders (DSM-5 (from 2013) or its predecessors) as some material is not included in the ICD (the ICD is also broader in scope, covering general as well as mental health). There remain differences, for example Rett disorder was included in ASD in the DSM-5 but in the ICD-11 it was excluded and placed in the chapter for Developmental Anomalies. Both the ICD and the DSM have been under revision and there has been collaborative work towards a convergence of the two since 1980 (when DSM-3 was published and ICD-9 was current), including more rigorous biological assessment - in place of historical experience - and a simplification of the system of classification. DSM The American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders version 5 (DSM-5), released in May 2013, is the current version of the DSM, and is the first to define ASD as a single diagnosis. ASD encompasses previous diagnoses which included Asperger disorder, childhood disintegrative disorder, PDD-NOS, and the range of diagnoses which included the word autism. Rather than distinguishing between these diagnoses, the DSM-5 adopted a dimensional approach to diagnosing disorders that fall underneath the autistic<unk>  umbrella because some proposed that individuals on the<unk>  were better represented as a single diagnostic category. Within this category, the DSM-5 includes a framework that differentiates each individual by dimensions of severity, as well as by associated features (i.e., the presence of other disorders or factors which likely contribute to the symptoms, other neurodevelopmental or mental disorders, intellectual disability, or language impairment). Another change included collapsing social and communication deficits into one domain. Thus, an individual with an ASD diagnosis would be described in terms of severity of social communication symptoms, severity of fixated or restricted behaviors or interests, and hyper- or hyposensitivity to sensory stimuli. The restricting of onset age was also loosened from 3 years of age to "early developmental period", with a note that symptoms may manifest later when social demands exceed capabilities.
Autism spectrum
Tardive dysmentia
Outline of autism
Nonverbal autism
Multiple complex developmental disorder
High-functioning autism
Low-functioning autism
Zellweger spectrum disorders