the frequency of "extra" (non-goal-directed) movements was more than 3 times higher in tic disorder patients than in people without a tic disorder, vocalizations were > 22 times more frequent, obsessive-compulsive and depressive symptoms were much more common
Tic assessment
Functional tics
\citet{Arbuckle_2022} present new data from the Washington University New Tics study on clinical features in children examined, on average, 4 months after tic onset, who would go on to be diagnosed with TS / CTD. They compare these characteristics to those described in 17 reports on functional tic-like symptoms (FND-tic). "Stark differences in presentation distinguish the FND-tic patients from typical PTD." Symptoms that best distinguished the groups included movements or vocalizations that were dramatically worse in the presence of others, vs. alone, coprophenomena at presentation, symptoms that dramatically and persistently disrupt the person’s intended actions or communications, and "tic attacks."
\citet{pringsheim2022} summarized typical clinical features of 180 children with primary tic disorders in the registry from Calgary, AB, Canada. Relevant for comparing to functional tic-like behaviors.