Mackenzie 2011.

Methods	4‐arm, single‐blind, placebo‐controlled randomised trial.
Participants	Study reports on participants undergoing a medical induction of labour. 105 nulliparous, singleton pregnancy, fetal cephalic presentation, intact membranes, undergoing labour induction using vaginal prostaglandins, low amniotomy for prolonged gestation or mild hypertension. All groups: subsequent pain management including aromatherapy, TENS and parenteral opioids, and regional blockade was provided when requested or recommended by the attending midwife or obstetrician.
Interventions	Experimental intervention Manual acupuncture – needles stimulated by hand for 30 minutes. Electro‐acupuncture – needles attached to an electrical stimulator and stimulated for 30 minutes. Commenced in both groups after medical induction initiated but before painful contractions started. Acupuncture provided by qualified registered acupuncturists. Needles inserted intramuscularly to depth of 15‐20 mm until unusual sensation (de qi) developed, needles remained inserted for 30‐60 minutes. Points used: LI 4, SP6, BL60 and BL67. Control/Comparison intervention Sham acupuncture – manual and electro 1:1 ratio – acupuncture stimulation not provided. Needles inserted adjacent to the specific acupuncture site – insufficient to provoke de qi sensation. Sham manual received no stimulation, sham electro were connected to the electrical stimulator but current not activated. Usual intrapartum care.
Outcomes	Primary outcome: rate of intrapartum epidural anaesthesia. Secondary outcomes: parenteral analgesia requirement, duration of labour, mode of birth, neonatal condition, postpartum haemorrhage.
Notes	Study duration: August 2005 to February 2009. Funding: supported by a grant from the Oxfordshire Health Services Research Committee and the Uterine Contractility Trust fund, held by the Oxford Radcliffe NHS Trust. Conflict of interest: authors state there are no conflicts of interest, except 1 author (IM) who provides legal opinion in litigation cases at the request of claimants and defendants. Setting: John Radcliffe Hospital. Country: UK. Manual and electro‐acupuncture were combined in the analysis due to the reporting of data in the manuscript for some outcomes.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated random numbers. Variable block sizes used.
Allocation concealment (selection bias)	Low risk	Allocation concealment by sealed opaque envelopes.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants blinded in 2 groups, except for the usual care group. Interventions were substantially different and obvious to an observer.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinded.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Does not describe.
Selective reporting (reporting bias)	Unclear risk	No published protocol.
Other bias	Low risk	No baseline imbalances.