A. Persistent deficits in social communication and social interaction across multiple contexts, as manifested by the following, currently or by history
A1. Deficits in social-emotional reciprocity, ranging, for example, from abnormal social approach and failure of normal back- and- forth conversation; to reduced sharing of interests, emotions, or affect; to failure to initiate or respond to social interactions.
A2. Deficits in nonverbal communicative behaviours used for social interaction, ranging, for example, from poorly integrated verbal and nonverbal communication; to abnormalities in eye contact and body language or deficits in understanding and use of gestures; to a total lack of facial expressions and nonverbal communication.
A3. Deficits in developing, maintaining, and understanding relationships, ranging, for example, from difficulties adjusting behaviour to suit various social contexts; to difficulties in sharing imaginative play or in making friends; to absences of interest in peers.
B. Restricted, repetitive patterns of behaviour, interests, or activities as manifested by at least 2 of 4 symptoms currently or by history
B1. Stereotyped or repetitive motor movements, use of objects, or speech (e.g., simple motor stereotypies, lining up toys or flipping objects, echolalia, idiosyncratic phrases).
B2. Insistence on sameness, inflexible adherence to routines, or ritualized patterns of verbal or nonverbal behaviour (e.g. extreme distress at small changes, difficulties with transitions, rigid thinking patterns, greeting rituals, need to take same route or eat same food everyday).
B3. Highly restricted, fixated interests that are abnormal in intensity or focus (e.g., strong attachment to or preoccupation with unusual objects, excessively circumscribed or preservative interest).
B4. Hyper- or hyporeactivity to sensory input or unusual interest in sensory aspects of the environment (e.g., apparent indifference to pain/temperature, adverse response to specific sounds or textures, excessive smelling or touching of objects, visual fascination with lights or movement)
C. Symptoms must be present in the early developmental periods (but may not become fully manifest until social demands exceed limited capacities, or may be masked by learned strategies in later life)
D. Symptoms cause clinically significant impairment in social, occupational, or other important areas of current functioning. (minimum = level 1)
Social Communication Severity Level (1, 2, or 3)
Restricted Repetitive Behaviour Severity Level (1, 2, or 3)
E. These disturbances are not better explained by intellectual disability (intellectual development disorder) or global developmental delay.
Levels of severity
|Severity Level for ASD||Social Communication||Restricted Interests & Repetitive Behaviours|
‘Requiring very substantial support’
|Severe deficits in verbal and nonverbal social communication skills cause severe impairments in functioning, very limited initiation of social interactions, and minimal response to social overtures from others. For example, a person with few words of intelligible speech who rarely initiates interaction and, when he or she does, makes unusual approaches to meet needs only and responds to only very direct social approaches.||Inflexibility of behaviour, extreme difficulty coping with change, or other restricted/repetitive behaviours markedly interfere with functioning in all spheres. Great distress/difficulty changing focus or action.|
|Marked deficits in verbal and nonverbal social communication skills; social impairments apparent even with supports in place; limited initiation of social interactions; and reduced or abnormal response to social overtures from others. For example, a person who speaks simple sentences, whose interaction is limited to narrow special interest, and who has markedly odd nonverbal communication.||Inflexibility of behaviour, difficulty coping with change, or other restricted/ repetitive behaviours appear frequently enough to be obvious to the casual observer and interfere with functioning in a variety of contexts. Distress and/or difficulty changing focus or action|
|Without supports in place, deficits in social communication cause noticeable impairments. Difficulty initiating social interactions, and clear examples of atypical or unsuccessful response to social overtures of others. May appear to have decreased interest in social interactions. For example, a person who is able to speak in full sentences and engages in communication but whose to-and-fro conversation with others fails, and whose attempts to make friends are odd and typically unsuccessful||Inflexibility of behaviour causes significant interference with functioning in one or more contexts. Difficulty switching between activities. Problems of organization and planning hamper independence.|
American Psychiatric Association. Pervasive developmental disorders. In: Diagnostic and Statistical Manual of Mental Disorders. 5th ed.-text revision (DSM-5). Washington, DC: American Psychiatric Association; 2013.