| Jukka Ylikoski15) (2017) | tVNS(97)- A tVNS instrument : consisting of one ear clip electrode connected to a wired neurostimulating device(’SaluSTIM’, Vagus Medical Inc, Helsinki, Finland)- intensity : 0.1–130㎃ / frequency : 25㎐ / pulse duration : 250㎲ | - | - | 60–90 min daily, 5 days a week |
| Liyan Peng16) (2018) | Auricular acupoints(8)- taVNS on auricular acupoints : Kindey(CO10), Yidan(CO11), Liver(CO12) and Shenmen(TF4) in the left ear | Anterior stimulation group(8)- stimulate at the anterior wall of the auditory canal and left lower limb(left middle shank) | Sham group(8)- taVNS at the left ear lobe and tail of the helix(8) | For 420s started with a baseline lasting for 60s.- This was followed by a first stimulation period of 30s and a break/baseline of 60s. Four alternating stimulation and baseline sequences were performed in total. |
| - Instrument : transcutaneous electrical nerve stimulation device(TENS200, HUATUO GmbH, Hangzhou, China)- intensity : around 5(varied individually between 4 and 8㎃) / frequency : 20㎐ / pulse width : 250㎲ |
| Jian-feng Tu17) (2019) | Deep acupuncture(DA) group(15)- the depth of acupuncture : 10㎜ to 30㎜- Quick twirling, lifting and thrusting weremanipulated for De qi. | Shallow acupuncture(SA) group(15)- the depth of acupuncture : approximately 2㎜- no needle manipulation for De qi | - | 6 acupuncture sessions(20 min) over three weeks(a period of 3 weeks, at a frequency of 2 sessions per week) |
| Acupoints : GV20, GV24, bilateral SJ5, GB41. GB2(bilaterally needled for patients with bilateral tinnitus, whereas only GB2 of the affected side was selected for patients with unilateral tinnitus) |
| Jukka Ylikoski18) (2020) | TCPT(171)- hearing, counseling, sound therapy, sleep module and tVNS- A tVNS instrument : consisting of one ear clip electrode connected to a wired TENS-neurostimulating device(Salustim, Helsinki Ear Institute)- The clip-electrode was placed on the tragus of the left ear- intensity : 0.3–30㎃ / frequency : 25㎐ / pulse duration : 250㎲ | - | - | 60–90 min daily, 5 days a week |