Criteria - all of the following:
(1) severe impairment in reciprocal interaction (see below)
(2) all absorbing narrow interest in a subject (see below)
(3) stereotypic imposition of routines and interests (see below)
(4) speech and language problems (see below)
(5) nonverbal communication problems (see below)
(6) motor clumsiness, with poor performance on a neuro-developmental examination
Impairment of reciprocal interaction - 2 or more of the following:
(1) unable to interact with peers
(2) lack of desire to interact with peers
(3) fails to appreciate social cues, with odd or inappropriate behavior
Narrow interest - 1 or more of the following:
(1) goes to extremes and excludes other activities
(2) adhered to a repetitive way
(3) rote learning more than understanding
Imposition of routines - 1 or both of the following:
(1) on self
(2) on others
Speech and language problems - 3 or more of the following:
(1) delayed speech or language development
(2) superficially perfect expressive language
(3) formal, pedantic language
(4) flat, staccato-like prosody or peculiar voice characteristics
(5) impaired language comprehension (misinterprets literal or implied meanings, other)
Nonverbal communication problems - 1 or more of the following:
(1) limited use of gestures
(2) clumsy or gauche body language
(3) limited facial expressions
(4) inappropriate facial expressions
(5) a peculiar, stiff gaze