Comparison of Swiss versus Standard Acupuncture in Patients with Chronic Low Back Pain. A Study Protocol for a Randomized, Controlled, Single-Blind, Parallel Trial

INTRODUCTION: Chronic low back pain (CLBP) cannot sufficiently be treated by pharmacological therapy and generates substantial health-care costs worldwide. Acupuncture, a cost-effective, safe and non-pharmacological therapy, has shown promising results in relieving acute low back pain; however, the optimal acupuncture therapy for CLBP remains controversial. This study will compare two acupuncture methods for pain relief in CLBP. METHODS AND ANALYSIS: This randomized, controlled, single-blind, parallel trial will be conducted in patients with clinically diagnosed CLBP with a disease duration ≥3 months and an average pain intensity of ≥4 points on an 11-point Pain Intensity Numerical Rating Scale (pain-NRS) on the previous 7 days. Patients will be randomized to 9-week acupuncture therapy using Jiu Gong Points (termed Swiss low back acupuncture, SLBA) or standard acupuncture (SA) therapy (weeks 1–6: two sessions/week, weeks 7–9: one session/week, 15 sessions/patient in total). Measurements will be conducted before the first session (T1), at the end of the 9-week therapy (T2) and after 3- and 6-month follow-up (T3 and T4). The primary hypothesis is that 9 weeks of SLBA will be superior in reducing the pain severity assessed by the pain-NRS compared to SA therapy for CLBP. Secondary outcomes will be derived from the Short-Form 36, Oswestry Disability Index, Multidimensional Pain Inventory questionnaire, Symptom Checklist-90 – Revised questionnaire and a daily pain diary. Assuming a minimal clinically important difference in the pain-NRS of 0.39 and an effect size of ≥0.6 between SLBA and SA, 80% power, 0.05 alpha level and 20% dropouts, a total of 55 patients/arm will be required. The primary outcome will be analyzed in the intention-to-treat population using chained linear regression models. Patients, outcome assessors and data analysts will be blinded to the treatment arm. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT05232487.