Author contributions
RGH was Chief Investigator. WB, VW, NH, TJP, SN, ADB, AM, JB, DW and CE were co-applicants on the grant application to the NIHR. All named above were also involved in the design, delivery and interpretation of the longer-term follow-up study. WB was the Trial Manager. BS and TJP were responsible for the statistical analysis. LZ and SN were responsible for the economic evaluation. WB, BS, SN and LZ have accessed and/or verified the underlying data. WB drafted the manuscript; all authors revised it for important intellectual content and approved the final manuscript.