1 Department of Obesity Medicine and Endocrinology, Salford Royal NHS Foundation Trust and University Teaching Hospital, Salford, UK. rpn@liverpool.ac.uk.
2 Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK. rpn@liverpool.ac.uk.
3 Diabetes Centre, St Helens Hospital, Marshalls Cross Road, St Helens, WA9 3DA, UK. rpn@liverpool.ac.uk.
4 Department of Obesity Medicine and Endocrinology, Salford Royal NHS Foundation Trust and University Teaching Hospital, Salford, UK.
5 Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK.