Dennis 2002a.

Methods	Setting: Toronto, Canada. Recruitment: Participants recruited from 2 semi‐urban community hospitals. Randomisation: RCT 2 arm. This study explicitly drew on the definition of peer support by Dennis as "the provision of emotional, appraisal and informational assistance by a created social network member who possesses experiential knowledge of a specific behaviour or stressor and similar characteristics as the target population" (Dennis 2003a). Peer training: There was a two and a half hour orientation session where the researcher described the study and answered questions. Training was three sessions, each of three hours duration on the prevention and treatment of problems relating to breastfeeding. There were also monthly support meetings.
Participants	256 breastfeeding first‐time mothers from 2 semi‐urban community hospitals near Toronto.
Interventions	Intervention: Peer volunteers were asked to contact the new mother within 48 hours after hospital discharge. Frequency of contact was not standardized in order to individualize the intervention to the mother's specific needs and to give credibility to the peer volunteer's experiential knowledge. Caller: Calls were made by peer supporters but timing was negotiated with the recipient and calls were made as often as the mother deemed necessary. Control group: Women allocated to the control group had access to the conventional in‐hospital and community post‐partum support services.
Outcomes	Physical health outcomes: none reported. Psychological health outcomes: none reported. Behavioural outcomes: breastfeeding, breastfeeding duration ‐ self report (questionnaire developed for use in study (not validated). Social health outcomes: none reported. Impact on participants: maternal satisfaction with infant feeding method, perceptions of peer support. (questionnaire developed for use in study ‐ self report (not validated)). Impact on peer supporter: volunteer perceptions (questionnaire developed for use in study ‐ self report (not validated)). Method of assessing outcome measures: phone survey
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk	Quote: ".....randomly generated numbers constructed by a biostatistician who was not involved in the recruitment process."
Allocation concealment?	Low risk	A ‐ Adequate, Quote: "Randomization was achieved using consecutively numbered, sealed opaque envelopes..."
Blinding? Participants	Unclear risk	Unclear.
Blinding? Providers	Unclear risk	Unclear.
Blinding? Outcome assessors	Low risk	Quote: "A research assistant blinded to group allocation telephoned all participants at 4, 8 and 12 weeks post partum to collect data..."
Blinding? Data analysts	Low risk	Quote: " Data were entered...by 2 research assistants blinded to group allocation."
Incomplete outcome data addressed? All outcomes	Low risk	Quote: "....an 'intention to treat' approach was used to analyse the data."
Free of selective reporting?	Low risk	All outcomes reported.