1 From the Management and Innovation for Longevity in Elderly Surgical Patients (MILES), Department of Surgery, National University of Singapore.
2 Quality, Innovation & Improvement and Department of Surgery, Ng Teng Fong General Hospital & Jurong Community Hospital.
3 Perioperative Medicine for Older People Undergoing Surgery (POPS), Department of Ageing and Health, Guy's and St Thomas' National Health Service Foundation Trust, London, United Kingdom.
4 School of Life Course and Population Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom.
5 Division of Surgery and Interventional Science, University College London, London, United Kingdom.