[1] Queens Univ Belfast, Sch Nursing & Midwifery, Belfast BT12 6BN, Antrim, North Ireland
[2] Queens Univ Belfast, Ctr Publ Hlth, Belfast BT12 6BN, Antrim, North Ireland
[3] Belfast Hlth & Social Care Trust, Royal Matern Hosp, Reg Neonatal Unit, Belfast, Antrim, North Ireland
[4] Queens Univ Belfast, Ctr Infect & Immun, Belfast BT12 6BN, Antrim, North Ireland