University of Oxford - Health Economics Research Centre (HERC), University of Oxford - Health Economics Research Centre (HERC), Imperial College London - NIHR Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, University College London - Centre for Behaviour Change (CBC), University College London - Centre for Behaviour Change (CBC), University of Oxford - Health Economics Research Centre (HERC), University of Oxford - NIHR Health Protection Research Unit in Healthcare Associated Infection and Antimicrobial Resistance, Government of the United Kingdom - Public Health England, University of Oxford - NIHR Health Protection Research Unit in Healthcare Associated Infection and Antimicrobial Resistance, University of Oxford - NIHR Health Protection Research Unit in Healthcare Associated Infection and Antimicrobial Resistance, University of Oxford - Nuffield Department of Medicine, University of Oxford, Nuffield Department of Medicine, John Radcliffe Hospital, University of Oxford - Nuffield Department of Population Health, University of Oxford - Department of Primary Care Health Sciences and University of Oxford, Nuffield Department of Medicine, John Radcliffe Hospital