Cluster randomised controlled trial of a financial incentive for mothers to improve breast feeding in areas with low breastfeeding rates: the NOSH study protocol. - Relton C; Strong M; Renfrew MJ; Thomas K; Burrows J; Whelan B; Whitford HM; Scott E; Fox-Rushby J; Anoyke N; Sanghera S; Johnson M; et al. (BMJ open, 2016)