Is transcutaneous auricular vagus nerve stimulation effective and safe for primary insomnia? A PRISMA-compliant protocol for a systematic review and meta-analysis

• Ting Yang ,

  Contributed equally to this work with: Ting Yang, Yunhuo Cai

  Roles Writing – original draft

  Affiliation Department of Nursing, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou City, China

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• Yunhuo Cai ,

  Contributed equally to this work with: Ting Yang, Yunhuo Cai

  Roles Writing – original draft

  Affiliation Department of Rehabilitation, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou City, China

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• Xingling Li,

  Roles Investigation, Writing – review & editing

  Affiliation Department of Acupuncture and Moxibustion, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou City, China

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• Lianqiang Fang ,

  Roles Conceptualization, Writing – review & editing

  * E-mail: 413351308@qq.com (HH); fanglianqiang21@163.com (LF)

  Affiliation Department of Acupuncture and Moxibustion, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou City, China

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• Hantong Hu

  Roles Conceptualization, Writing – review & editing

  * E-mail: 413351308@qq.com (HH); fanglianqiang21@163.com (LF)

  Affiliation Department of Acupuncture and Moxibustion, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou City, China

  https://orcid.org/0000-0001-8759-5083

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