Epidemiological studies on the prevalence of tic disorders in children
| First author, year (ref) | Country | Age (y) | Screening procedure | Sample size | Mannerisms and stereotypies | Point prevalence (%) | Period prevalence (%) |
|---|---|---|---|---|---|---|---|
| Modified from Shapiro et al.1 | |||||||
| Boncour, 19101 | France | 2–13 | Teacher observation | 1759 | + | 23.7 | |
| MacFarlane, 19542 | USA | 1–14 | Parent interview | 116 | + | − | 25 |
| Lapouse, 19643 | USA | 6–12 | Parent interview | 482 | + | 12 | − |
| Pringle, 19674 | UK | 7 | Parent questionnaire | 7949 | + | 7.7 | − |
| Medical history and examination | 7958 | 5.2 | − | ||||
| 7965 | 4.1 | − | |||||
| Rutter, 19705 | UK | 9–12 | Parent and teacher interview | 2057 | + | ||
| Non-psychiatric sample | 1919 | 4 | − | ||||
| Psychiatric sample | 95 | 18 | − | ||||
| Non-psychiatric epileptic sample | 26 | 8 | − | ||||
| Psychiatric epileptic sample | 17 | 24 | − | ||||
| Shepherd, 19716 | UK | 5–15 | Parent questionnaire | 6290 | + | − | 20 |
| Achenbach, 1978–97,8 | USA | 6–16 | Parent questionnaire | 2200 | − | ||
| Population sample | 1100 | 7.7 | − | ||||
| Referral sample | 1100 | 28.8 | − | ||||
| Caine, 19889 | USA | 5–18 | Parent interview | ||||
| Physicians | |||||||
| Other health professionals | 41 | + | − | 0.03 | |||
| School personnel | |||||||
| Local news media | |||||||
| Medical history and examination | |||||||
| Comings, 199010 | USA | 7–14 | Classroom observation; teacher and/or parent interview | 3034 | − | 1.4 | − |
| Kurlan, 199411 | USA | 9–15 | Parent questionnaire and medical examination | 70 | − | ||
| Normal classes | 35 | 4.9 | − | ||||
| Special classes | 35 | 21.9 | − | ||||
| Mason, 199812 | UK | 13–14 | Parent questionnaire | 111 | − | 18 | − |
| Pupil questionnaire | 152 | ||||||
| Teacher questionnaire | 147 | ||||||
| Classroom psychologist observation | 166 | − | |||||
| Present study | Italy | 6–11 | Teacher observation (after training) | 2347 | − | − | 2.9 |