Authors’ contributions
EB drafted the manuscript and managed the co-ordination of the study. WH conceived of the study, led in its design and co-ordination, and contributed to the writing of the manuscript. MD led in the co-ordination of the study, contributed to the study design, and contributed to the writing of the manuscript. CC participated in the design of the study and its statistical analysis. RW co-ordinated the statistical aspects of the trial. RO participated in the design of the study and led on health economic component of the study. JM participated in the design of the study and led on the qualitative research component of the study. AK and CH managed the co-ordination of the trial. LR provided vital personal and public involvement input to the study. All authors read and approved the final manuscript.