Author contributions
N.P. and P.M. developed the study protocol, led the study and wrote the manuscript. K.R. developed the study protocol, led the study and reviewed the manuscript. K.W. developed and led the qualitative study, analysed the data and wrote the manuscript. M.P. undertook the qualitative study, analysed the data and wrote the manuscript. J.P. developed the study protocol, oversaw the study implementation and edited the manuscript. A.B. managed the study, completed ethical review and data collection and reviewed the manuscript. G.M. managed the study, co-ordinated site implementation, undertook data collection and helped to write the manuscript. P.V.-S. developed the study database, co-ordinated data collection and analysis, and helped to write the manuscript. T.G. developed the microbiology protocol, contributed to the analysis and edited and reviewed the manuscript. L.N.T., R.S. advised on study protocol, reviewed progress and edited the manuscript. I.S. provided patient perspectives and reviewed the study protocol, documents and overall progress. R.G.F. and D.H. helped to develop study protocol and oversaw the statistical analysis and modelling for a definitive study. B.C. advised on study protocol, reviewed progress and edited the manuscript. J.M. advised on study protocol and acquisition of the SDD formulation, reviewed progress and reviewed the manuscript.