Table 1.
Epidemiological Studies on the Prevalence of Tic Disorders in Children
| First Author, Year | Country | Age (Years) | Screening | Sample Size | Point Prevalence (%) | Period Prevalence (%) |
| Boncour, 191059 | France | 2–13 | Teacher observation | 1759 | 23.7 | – |
| MacFarlane, 195426 | USA | 1–14 | Parent interview | 116 | – | 25 |
| Lapouse, 196427 | USA | 6–12 | Parent interview | 482 | 12 | – |
| Pringle, 196728 | UK | 7 | Parent questionnaire, medical history and examination | 7949 | 7.7 | – |
| 7958 | ||||||
| 7965 | ||||||
| Rutter, 197060 | 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, 197161 | UK | 5–15 | Parent questionnaire | 6290 | – | 20 |
| Achenbach, 1978–930,31 | USA | 6–16 | Parent questionnaire | 2200 | ||
| Population sample | 1100 | 7.7 | ||||
| Referral sample | 1100 | 28.8 | ||||
| Kurlan, 200144 | USA | 8.5–17.5 | Parent questionnaire | |||
| Technician exam | ||||||
| Special education | 341 | 29 | ||||
| Regular education | 1255 | 17.9 | ||||
| Khalifa, 200350 | Sweden | 7–15 | Parent questionnaire | |||
| Medical exam | ||||||
| Regular education | 4438 | 6.3 | ||||
| Special education | 41 | 46.3 | ||||
| Lanzi, 200422 | Italy | 6–11 | Teacher observation | 2347 | 2.9 | |
| Ooki, 200533 | Japan | 3–15 | Questionnaire | 1986 | 6.8 (males)4.1 (females) | |
| Linazasoro, 200662 | Spain | 4–16 | Parent and teacher questionnaireObservation | 867 | 6.5 | |
| Stefanoff, 200724 | Poland | 12–15 | Parent and teacher questionnaireExam | 1579 | 6.7 | 9.9 |
| Schlander, 200936 | Germany | 0–50+ | Database code | 2.238.460 | 0.2 | |
| Cubo, 201148 | Spain | 6–16 | Parent, teacher questionnaire | |||
| Observation | ||||||
| Neurologist interview | ||||||
| Regular education | 741 | 16.8 | ||||
| Special education | 54 | 20.3 |
Table 2.
Screening Instruments vs. Gold Standard in Mainstream Schools
| N = 63 | Sensitivity % 95% CI | Specificity % 95% CI | PPV% 95% CI | NPV% 95% CI | +LR ratio 95% CI |
| Teachers | 40 (9.64–70.36) | 74 (59.81–88.77) | 30 (5.68–55.86) | 81 (67.73–94.77) | 1.64 (0.55–4.87) |
| Parents | 58 (30.44–86.92) | 92 (86.35–99.61) | 63 (35.21–92.07) | 91 (68.08–87.80) | 7.38 (2.85–19.87) |
| Observers | |||||
| 1 hour | 33 (6.66–60.00) | 80 (68.30–90.88) | 28 (4.91–52.23) | 83 (72.24–93.72) | |
| 2 hours | 58 (30.44–86.22) | 80 (68.30–90.88) | 41 (17.78–64.58) | 89 (79.26–98.02) | 2.9 (1.37–5.93) |
| 3 hours | 58 (30.44–86.22) | 78 (65.87–89.23) | 39 (16.37–61.45) | 88 (78.79–97.95) | |
| Multiple sources | |||||
| Teachers+ parents +2-hour ob. | 92 (76.03–100) | 65 (51.59–77.83) | 38 (20.27–55.59) | 97 (91.38–100) | 2.59 (1.72–3.90) |
| Teachers+parents | 83 (62.24–100) | 74 (62.55–86.47) | 43 (23.22–63.74) | 95 (88.25–100) | 3.26 (1.91–5–57) |
| Teachers+2-hour ob. | 67 (40.00–93.34) | 70 (57.30–82.70) | 35 (15.32–54.24) | 90 (80.22–99.26) | 2.22 (1.24–3.97) |
| Parents + 2-hour ob. | 92 (76.03–100) | 72 (60.30–84.80) | 44 (24.54–63.46) | 97 (92.28–100) | 3.33 (2.07–5.38) |
Data obtained from Cubo et al, study.48
Table 3.
Screening Instruments vs. Gold Standard in Special Education Settings
| N = 57 | Sensitivity % 95% CI | Specificity % 95% CI | PPV% 95% CI | NPV% 95% CI | +LR ratio 95% CI |
| Teachers | 73 (46.41–99.05) | 55 (41.04–70.08) | 28 (11.84–45.30) | 76 (61.14–90.38) | 1.63(1.00–2.66) |
| Parents | 36 (7.93–64.79) | 42 (27.79–56.65) | 27 (9.87–43.97) | 87 (74.51–98.83) | 0.62 (0.27–1.42) |
| Observers | |||||
| 1 hour | 27(0.95–53.59) | 55 (41.04–70.08) | 13(–0.72–26.80) | 76 (61.14–90.38) | |
| 2 hours | 36 (7.93–64.79) | 44 (29.92–58.96) | 14 (1.24–26.34) | 74 (57.54–90.60) | 0.65(0.28–1.49) |
| Multiple sources | |||||
| Teachers+ parents +2-hour ob. | 73 (39.02–93.97) | 58 (36.77–78.60) | 42 (20.25.66.50) | 83 (58.58–96.42) | 1.02 (0.74–1.40) |
| Teachers+ parents | 73 (39.02–93.97) | 29 (16.07–43.03) | 22 (9.56–35.44) | 87 (69.47–100) | 1.15 (0.82–1.62) |
| Teachers+ 2-hour ob. | 73 (39.02–93.97) | 35 (21.56–49.54) | 23 (10.16–37.20) | 89 (74.37–100) | 1.26 (0.89–1.80) |
| Parents + 2-hour ob. | 45 (30.00–60.36) | 22 (10.07–34.36) | 12 (2.25–22.74) | 62 (38.77–86.22) | 0.58 (0.30–1.13) |
Data obtained from Cubo et al, study.48