## 3 Results
### Results of Syntheses  
The effectiveness of CBIT treatment was specifically investigated in two studies [15; 31]. One study [15] reported a significant reduction in the YGTSS Total Tic score after the CBIT intervention with a decrease of 7.6 points in the experimental group from baseline to post-treatment. Instead, the control group showed only a 3.5 points reduction in the YGTSS Total Tic score between the two evaluations. Conversely, in the second study [31], an initial increase in the YGTSS Total Tic score was observed in both the experimental and the control group at the first assessment post-intervention, followed by a significant decrease at the follow-up (especially in the experimental group). Trends were different for motor tics, vocal tics, and level of impairment: motor tics and level of impairment significantly decreased in the subjects of the group-based CBIT (a reduction of 32% of motor tics was observed immediately after the CBIT and was maintained at the 3-month follow-up), as well as in the control group (the reduction of 42.8% in motor tics after the psychoeducation was followed by an increase of 76.5%). Instead, a significant increase in vocal tics was observed in both the group-based CBIT (+106%), and the control group (+107%) at the first assessment post-intervention, followed by a significant decrease at the follow-up (with vocal tics decreasing by 65.7% in the group-based CBIT and by 74.8% in the EIT group). Another article [30] investigated the efficacy of Habit Reversal Training (HRT), compared to an educational intervention. The findings indicated a significant improvement in the Motor Tics score for the HRT group, while no improvement was observed in the Vocal Tic Severity subscale. These results suggest that HRT may yield greater improvements in motor tics, compared to the educational intervention [30]. One article examined the efficacy of an intensive Exposure and Response prevention Program (ERP), called \"Tackle your Tics\" (TYT) [29]. In this study, the intervention group received TYT treatment, while the control group had to wait three months before receiving the same intervention. The YGTSS total tic score showed a reduction of 3.14 points in the TYT group. The waiting-list group exhibited a spontaneous reduction in tic severity duringthe waiting period, and after receiving the treatment, there was a 2.85 points reduction in the YGTSS total tic score. Furthermore, no significant group differences were found in the mean decrease of motor and vocal tics, with both scores showing significant reductions [29]. The remaining studies [18; 19; 20; 21] investigate the effectiveness of behavioral treatments administered via telehealth or the Internet. These studies examined CBIT delivered via telehealth [18], CBIT provided through Voice over Internet Protocol (VoIP) [19], Internet-based CBIT (ICBT) [20], and Internet-delivered ERP [21]. The findings support the hypothesis that CBIT can be an effective intervention even when administered in an Internet-based way. For telehealth-administered CBIT, the YGTSS Total Tic Severity score decreased by 7.8 points at post-treatment, compared to a 6.5 point reduction following face-to-face CBIT [18]. The slight difference suggests that CBIT can be effectively administered via telehealth without a loss of efficacy. Regarding CBIT-VoIP, a significant difference was found between the Total Tic score at baseline versus post-treatment, with a decrease of 7.25 points at post-treatment, compared to a reduction of only 1.75 points in the control group [19]. This statistically significant difference suggests the effectiveness of CBIT delivered via telematics. The Internet-based CBIT was also effective in treating young people with CTD [20]. This way of delivering CBIT resulted in a significant reduction in the YGTSS Motor Tic and Impairment score. Although there was no immediate improvement in the Vocal Tic Score post-treatment, a significant reduction in phonic tics was observed at follow-up [20]. The Internet-delivered ERP was also associated with improvements.