[1] Univ British Columbia, Sch Populat & Publ Hlth, Vancouver, BC, Canada
[2] SmartMom Mobile Hlth Educ, Vancouver, BC, Canada
[3] Univ British Columbia, Dept Obstet & Gynaecol, Vancouver, BC, Canada
[4] St Pauls Hosp, Ctr Hlth Evaluat & Outcome Sci, Vancouver, BC, Canada
[5] Univ British Columbia, Dept Family Practice, Birth Pl Lab, Vancouver, BC, Canada
[6] Univ British Columbia, Dept Family Practice, Vancouver, BC, Canada
[7] London Sch Hyg & Trop Med, Fac Publ Hlth & Policy, Publ Hlth Environm & Soc, London, England
[8] Univ British Columbia, Midwifery Program, Family Practice, Vancouver, BC, Canada
[9] Univ Calgary, Cumming Sch Med, Paediat, Calgary, AB, Canada
[10] Univ British Columbia, Vancouver, BC, Canada
[11] Univ Saskatchewan, Dept Community Hlth & Epidemiol, Saskatoon, SK, Canada
[12] Univ Toronto, Lawrence S Bloomburg Fac Nursing, Toronto, ON, Canada