Table 1.

World Health Organization Trial Registration Data

Data category	Information
Primary registry and trial identifying number	ClinicalTrials.gov NCT03180554
Date of registry in primary registry	08/06/2017
Secondary identifying numbers	Southeast Regional Health Authority, Norway, Project Number: 2017/766 Cristin Project ID: 619480
Source of monetary and material support	Southeast Regional Health Authority, Norway
Primary sponsor	Southeast Regional Health Authority, Norway
Contact for public queries	Charles Ethan Paccione, M.S., M.A., Ph.D. Fellow Email: charlespaccione@gmail.com
Contact for scientific queries	Charles Ethan Paccione, M.S., M.A., Ph.D. Fellow Email: charlespaccione@gmail.com Department of Pain Management and Research Oslo University Hospital, Ullevål
Public title	Body versus Machine: Meditative Breathing versus Vagus Nerve Stimulation in the Treatment of Chronic Widespread Pain
Scientific title	Body versus Machine: Motivational Nondirective Resonance Breathing versus Transcutaneous Vagus Nerve Stimulation in the Treatment of Fibromyalgia
Country of recruitment	Norway
Health condition studied	Chronic widespread pain, fibromyalgia
Interventions	Motivational nondirective resonance breathing (active and Sham) Transcutaneous vagus nerve stimulation (active and sham)
Key inclusion and exclusion criteria	Inclusion criteria: • Confirmatory diagnosis of chronic widespread pain, including fibromyalgia; widespread pain index (WPI) ≥ 7 and symptom severity scale (SSS) score ≥ 5 OR WPI of 4–6 and SSS score ≥ 9; generalized pain in at least 4 of 5 body regions must be present; pain symptoms have been generally present for at least 3 months; average pain intensity ≥ 6 on a 0–10 numerical rating scale, where 0 represents “no pain” and 10 represents the “worst pain imaginable” Exclusion criteria: • History and/or presence of comorbid severe neurological or psychiatric disorders (e.g., mania, psychosis, suicidality, bipolar/schizophrenia/autism spectrum disorders); neurodegenerative disorders (e.g., Parkinson’s, Alzheimer’s, Huntington’s disease); pregnancy or planned pregnancy; planned surgery; eating disorder (e.g., obesity, anorexia nervosa); head trauma; migraine; active heart implants (e.g., pacemaker); active ear implants (e.g., cochlear implant); individuals who have practiced meditation consistently (for more than 20 min/day) within the last 6 months
Study type	Randomized controlled clinical trial Interventional Allocation: randomized Intervention model: parallel assignment Masking: double blind (subject, caregiver, investigator, outcomes assessor) Primary purpose: treatment
Date of first enrolment	June 6, 2019
Target sample size	112
Recruitment status	Recruiting
Primary outcome	Heart rate variability (HRV)
Key secondary outcome	Numerical rating scale for average pain intensity; pain detection threshold; pain tolerance threshold; pressure pain limit; blood pressure; credibility/expectancy; health-related quality of life; stress and depression; interoceptive awareness; spirituality; catastrophizing; interference