“adult-onset dysfluency” rather than a neurodevelopmental disorder . Adult-onset dysflu-
encies are associated with specific neurologic al insults and a variety of medical conditions
and mental disorders and may be specified with them, but they are not a DSM-5 diagnosis. 
Tourette’s disorder. Vocal tics and repetitive vocalizations of  Tourette’s disorder
should be distinguishable from  the repetitive sounds of childhood-onset fluency disorder
by their nature and timing. 
Social (Pragmatic) Communication Disorder
Diagnostic Criteria 315.39 (F80.89)
A. Persistent difficulties in the social use of verbal and nonverbal communication as man-
ifested by all of the following:
1. Deficits in using communication for social purposes, such as greeting and sharing
information, in a manner that is appropriate for the social context.
2. Impairment of the ability to change communication to match context or the needs of
the listener, such as speaking differently in a classroom than on a playground, talk-
ing differently to a child than to an adul t, and avoiding use of overly formal language.
3. Difficulties following rules for conversation and storytelling, such as taking turns in
conversation, rephrasing when misunderstoo d, and knowing how to use verbal and
nonverbal signals to regulate interaction.