[1] Imperial Coll London, Div Psychiat, London, England
[2] Univ Cambridge, Fac Educ, Play Educ Dev & Learning PEDAL Res Ctr, Cambridge, England
[3] Imperial Coll London, Sch Publ Hlth, London, England
[4] Imperial Coll London, Imperial Clin Trials Unit, London, England
[5] Vrije Univ Amsterdam, Fac Behav & Movement Sci, Clin Child & Family Studies, Amsterdam, Netherlands
[6] Kings Coll London, Inst Psychol Psychiat & Neurosci, London, England
[7] Univ Surrey, Sch Psychol, Guildford, Surrey, England
[8] Netmums, Parent Supporter Serv, London, England
[9] Univ Oxford, Dept Psychiat, Oxford, England
[10] African Hlth Res Inst, Durban, South Africa
[11] Erasmus Univ, Dept Psychol Educ & Child Studies, Rotterdam, Netherlands
[12] Univ Warwick, Warwick Clin Trials Unit, Coventry, W Midlands, England