We've all been wrong about Provisional Tic Disorder

Background: Provisional Tic Disorder (PTD)—current tics, less than a year since onset—is a common childhood neuropsychiatric disorder. The received wisdom among clinicians is that PTD is short-lived and mild, with one or at most a few tics, and rarely includes complex tics, premonitory phenomena or comorbid illnesses. However, such conclusions come from clinical experience, with biased ascertainment and limited follow-up.
Methods: Prospective study of 89 children with tics starting 0-9 months ago (median 4 months), fewer than half from clinical sources. Follow-up at 12 (± 24, 36, 48) months after the first tic.
Results: Most had ADHD (39), an anxiety disorder (27), OCD (9) or enuresis (26). Autism spectrum symptom scores were not elevated. At the first study visit, all had at least two current tics, with a lifetime total of 6.7 motor and 2.2 phonic tics (mean). Forty had had a complex tic, and 69 could suppress some tics. Total tic score was > 13 in 62/89, YGTSS impairment score was ≥ 20 in 14/88, and 53/62 had recent or planned doctor visits for the tics.  At 12 months, 79 returned, and 78 still had tics. However, most (53/62) had no current plans to see a doctor for tics. At 12 months, history and extended examination revealed no tics in 37% of children, but tics were almost always observed via audio-visual recording when the child was seated alone. Most who returned at 2-4 years still had tics known to the child and family, but medical impact was low.
Conclusion: Our results do not contradict previous observations, but overturn clinical lore. The data strongly argue against the longstanding tradition of dividing tic disorders arbitrarily by duration.