Pointers to clinically differentiate tics from functional tic-like movements (both can coincide)
| Tics/Tourette syndrome (TS) (references) | Functional tic-like movements* | |
| Gender | M>F 4:14 | F>M 9:1 |
| Age of onset tics/tic-like movements (year) | 4–64 | 13.7 |
| Anxiety | 20%4 | 68% reported, clinically diagnosed in 50% |
| ASD | 5%–15%3 | 12% repor ted +57% clinically suspected (50% clinically diagnosed in subset of 14 GOSH patients) |
| CGAS | Mean 59 (SD 7.9)4 | Median 45 (range 35–75) |
| Waxing and waning | Often present | 32% |
| Premonitory urge | 77%4 | 62% † |
| Suppressibility | Often present | 59% |
| Pali/echo/copro-like phenomena | Coprolalia and copropraxia in 12.4%–28%5‡ | 77% |
| First tics started in head/neck/rostrocaudal presentation | 90%4 | 62% |
| Yale Global Tic Severity Score | Mean 254 | Mean 62.6 (SD 19) |
| Watching videos of ‘tics’ on social media | Unknown | 77% |
*Based on 34 patients presenting with functional tic-like movement to specialist tic clinics (1 October 2020–30 April 2021) in London, UK and Calgary, Canada.
†This study lacks qualitative data, and we can thus not differentiate the types of urges in this series from those described in patients with chronic tic disorders/TS.
‡In TS without comorbidity, coprolalia was seen in 10% and copropraxia in 2.4%. In TS with comorbidity, this was 21% and 7%, respectively (5).
ASD, autism spectrum disorder; CGAS, Children’s Global Assessment Scale; F, female; M, male.