Li 2017.

Study characteristics
Methods	Two‐arm RCT Number analyzed/randomized: 60/60 Statistical analysis: did not mention ITT analysis; Student's t‐test and Chi² test; power analysis not conducted Funding source: NR Not reported if ethical approval was obtained, but informed consent was obtained
Participants	Participant recruitment: recruitment at clinic at Department of Rehabilitation of a hospital in China Setting: recruitment clinic Inclusion criteria: 1) LBP > 3 months; 2) pain located between lower rib and the inferior gluteal folds, not below the knee; 3) negative response in straight‐leg raising test and intact on neurological examinations; 3) no meaningful positive findings on X‐ray image Exclusion criteria: 1) severe cardiac, or brain disease and severe psychosis, or combination; 2) LBP due to specific etiology, including lumbar tuberculosis, disc protrusion, disc stenosis, ankylosing spondylitis, spondylolisthesis, or tumor Age (mean): 42 years Gender (female): 47% Pain duration (mean): 2.1 years Pain intensity (mean): 6.1 (VAS, 0 to 10)
Interventions	1) GROUP 1: electroacupuncture (local + distance acupoints) Acupuncture points: shenshu, dachangshu, jiaji, cijiao, huantiao (all bilaterally) Depth: inserted vertically to a depth of 1 to 1.5 cm De Qi: elicited by manual stimulation and maintained for 30 min Sessions: 20 sessions (1/d for 20 d) Equipment setting: G6805‐1 equipment with continuous wave Acupuncturist experience: NR 2) GROUP 2: acupuncture (local acupoints) Acupuncture points: Ashi points Depth: inserting into the muscle De Qi: not mentioned Sessions: 10 sessions (1/d for 10 d) Co‐intervention: NR Duration of treatment: 10 to 20 days Duration of follow‐up: 6 months after the end of the sessions
Outcomes	1) Pain intensity: VAS (0 to 10) 2) Back‐specific function status: Oswestry disability index (ODI, 0 to 100%), lower values better Assessment times: immediately after, and 6 months after the end of sessions Costs: NR Adverse effects: NR
Notes	Conclusion: There was no difference between acupuncture at Ashi points and electroacupuncture for treatment of nonspecific LBP. Language: Chinese For results, see comparisons 5.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Table of random numbers was used.
Allocation concealment (selection bias)	Unclear risk	No mention of concealment methods
Blinding of participants (performance bias) All outcomes	Unclear risk	Not mentioned
Blinding of personnel /care providers (performance bias) All outcomes	High risk	Not possible
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not mentioned
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No participant dropped out during the follow‐up period.
Intention‐to‐treat‐analysis (attrition bias)	Low risk	The analyses were conducted according to their randomisation group.
Selective reporting (reporting bias)	Low risk	Both pain and function outcomes were reported.
Group similarity at baseline (selection bias)	Low risk	Baseline characteristics were similar between two groups.
Co‐interventions (performance bias)	Low risk	Authors did not mention if additional co‐interventions were given.
Compliance bias (performance bias)	Unclear risk	Study did not report compliance.
Timing of outcome assessments (detection bias)	Low risk	The outcomes were measured at the same time in both groups.
Other bias	Low risk	Not identified