1. Department of Applied Health Research, University College London, London, UK.
2. University of Bangor, Bangor, UK.
3. National Nursing Research Unit, Florence Nightingale School of Nursing and Midwifery, King’s College London, London, UK.
4. Centre for Patient Safety and Service Quality, Faculty of Medicine, Imperial College London, London, UK.
5. Florence Nightingale School of Nursing and Midwifery, King’s College London, London, UK.
6. Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.