Akbarzadeh 2014.

Methods	RCT
Participants	Pregnant women aged 18 to 35 years, with a singleton, term pregnancy, and healthy fetal membranes. No history of medical, surgical, or mental problems and no special problems during pregnancy. The participants’ uterine contractions started spontaneously and, at admission, the contractions occurred every 5 to 10 minutes and cervical dilatation was 3 to 4 cm
Interventions	The study was conducted in Shoushtari Hospital, Iran in 2012. In the supportive care group (N = 50), the doula was constantly beside the mother from the beginning of the mother’s maternity ward admission (beginning of the active phase of labour at 3 to 4 cm cervical dilatation) to the end of the second stage of labour. Supportive measures classified into psychological and emotional, educational, and physical categories were offered to the mother. Psychological and emotional support included touching, empathy, compassion, encouraging the mother to continue cooperation in the labour process, reassurance, taking mother’s hands, maintaining eye contact, creating a sense of trust and confidence, continuous talking, and reduction of fear during labour. Educational support included informing the mother about the natural process of childbirth and answering her questions. Finally, physical support included cooling the mother, satisfying her hunger and thirst, and helping her change the positions in various stages of labour. The control group (N = 50) received the department’s routine care and underwent no interventions
Outcomes	Pain assessment (before and after intervention) using the VAS. VAS is a scale numerated from 0 to 10 with 0, 1 to 3, 4 to 6, 7 to 9, and 10 representing no, mild, moderate, severe, and the worst possible pain. Mode of delivery (CS, VD)
Notes	For all women who received doula care in the intervention group, the doula was one researcher. Unknown if companions were typically permitted on the ward, if continuous EFM was used routinely, or if epidural anaesthesia was available Dates of study: 2012 Funding: The study was financially supported by the Research Center for Traditional Medicine and History of Medicine and the Research Vice‐Chancellor of Shiraz University of Medical Sciences, Shiraz, Iran. Conflicts of interest: The authors declare that they have no known conflict of interests.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Akbarzadeh 2015 and Masoudi 2014 specify the process of selecting blocks, "the subjects were selected through simple random sampling and were divided into supportive care, acupressure, and control groups using stratified block randomisation. In doing so, a number was randomly selected from the table of random numbers and the researcher moved toward the right or left column or row and wrote the 5 digit numbers down. Since the participants were divided into 3 groups in this study, 3‐therapy method was used and classification was performed as follows: A: supportive care group, B: acupressure group, and C: control group. Accordingly, ABC: 1, ACB: 2, BAC: 3, BCA: 4, CAB: 5, and CBA: 6. It should be noted that numbers 0, 7, and 9 were ignored".
Allocation concealment (selection bias)	Unclear risk	Unclear if central randomisation, sequentially numbered/opaque containers were used during allocation
Blinding of participants and personnel (performance bias) All outcomes	High risk	There is no mention of blinding of participants or personnel throughout this study, but blinding of participants and personnel is not possible
Blinding of outcome assessment (detection bias) All outcomes	High risk	The study data were collected using interview form (including demographic information, history of pregnancy, familial status, and pregnancy information), observation form (including evaluation of uterine contractions, fetal heart rate, labour progress, and delivery outcome), and VAS. VAS is a scale numerated from 0 to 10 with 0, 1 to 3, 4 to 6, 7 to 9, and 10 representing no, mild, moderate, severe, and the worst possible pain. High risk of bias for pain reporting in the intervention‐supportive care group, as pain is a subjective and self‐reported outcome and women would know whether they were in the intervention or control group. Low risk of bias for mode of delivery, as was assessed using observation and mode of delivery is an objective outcome
Incomplete outcome data (attrition bias) All outcomes	Low risk	From tables 1 and 2, it appears that there was no missing data from either outcome in the intervention or control group
Selective reporting (reporting bias)	Low risk	Important outcomes were included across the 3 references for this study
Other bias	Low risk	Low risk of other bias