1. Department of Endocrinology (S.R., A.S., J.U.W.), Queen Elizabeth Hospital, Gateshead, NE9 6SX, United Kingdom
2. Royal Free Hampstead National Health Service Trust (M.V.), London, NW3 2QG, United Kingdom
3. School of Clinical Medical Sciences (J.U.W., S.H.S.P.), Newcastle University, Newcastle upon Tyne, NE1 7RU, United Kingdom
4. Royal Victoria Infirmary (S.H.S.P.), Newcastle upon Tyne, NE4 6BE, United Kingdom