Summary of stimulation protocols details, treatment strategies and associated therapies
| Study | Intensity | Duration | Coil/electrode position | tDCS reference | Sham procedure | Psychological intervention | Treatment strategy | Medication |
|---|---|---|---|---|---|---|---|---|
| De Lima et al. (86) (2019) | 2 mA Electrode size 5 × 7 | 20 min | F3 | FP2 | 30 s | Not allowed | Monotherapy | Stable doses |
| Deppermann et al. (115) (2014) | 15 Hz 80% rMT | 3 min; 18 trains of 2 s | F3 | – | 90° from skull | Psychoeducation, 3 group sessions | Monotherapy | Stable doses for 3 wk |
| Diefenbach et al. (116) (2016) | 1 Hz 90% rMT | 15 min; 900 pulses per session | Individual structural MRI: x, y, z = 42, 36, 32 (MNI) | – | Sham coil | Not allowed | Monotherapy | Stable doses for 3 mo or stable benzodiazepines for 2 wk |
| Dilkov et al. (87) (2017) | 20 Hz 110% rMT | 20 trains, 9 s per train; 51 s intertrain interval | 5 cm rostral to motor cortex | – | 90° from skull, same intensity | Allowed | Monotherapy | Stable doses for 6 mo or no medications for at least 2 wk |
| Herrmann et al. (117) (2017) | 10 Hz 100% rMT | 40 trains of 4 s (1560 pulses; intertrain interval 26 s | FPZ | – | Sham coil | Virtual reality exposure | Augmentation | Not allowed |
| Huang et al. (118) (2018) | 1 Hz 90% rMT | 3 trains of 500 pulses; intertrial interval 10 min | P4 | – | Sham coil | Not allowed | Monotherapy | Stable doses for 3 mo |
| Mantovani et al. (119) (2013) | 1 Hz 110% rMT | 30 min | 5 cm anterior to motor cortex | – | Sham coil | Allowed | Monotherapy | Stable doses for 4 wk or no medication for 6–8 wk before |
| Movahed et al. (120) (2018) | 2 mA Electrode size NR | 20 min | F4 | Left deltoid | NR | Not allowed | Monotherapy | Not allowed |
| Nasiri et al. (121) (2020) | 2 mA Electrode size 5 × 5 | 30 min | F4 | Left deltoid | F3 | UP 12 sessions | Monotherapy | Not allowed |
| Notzon et al. (88) (2015) | 15 Hz 80% rMT | 3 min; 18 trains of 2 s | F3 | – | 90° from skull | Virtual reality exposure | Augmentation | Not allowed |
| Prasko et al. (122) (2007) | 1 Hz 110% rMT | 30 min | 5 cm rostral to motor cortex | – | 90° from skull, same intensity | NR | Monotherapy | Stable doses |
EEG = electroencephalogram; F3 = 10–20 EEG position corresponding to the left dorsolateral prefrontal cortex; F4 = 10–20 EEG position corresponding to the right dorsolateral prefrontal cortex; FP2 = 10–20 EEG position corresponding to the supraorbital region; FPZ = 10–20 EEG position corresponding to the ventromedial prefrontal cortex; MNI = Montreal Neurological Institute; NR = not reported; P4 = 10–20 EEG position corresponding to the right posterior parietal cortex; rMT = resting motor threshold; UP = unified protocol.