1. Division of Medical Sciences, University of Birmingham, Queen Elizabeth Hospital (J.S.M., M.C.S., P.M.S.), Edgbaston, Birmingham, United Kingdom B15 2TH
2. Department of Endocrinology, St. Bartholomew’s Hospital (J.P.M., G.K., P.P., G.M.B.), London, United Kingdom EC1A 7BE
3. Regional Endocrine Unit, Southampton University Medical School ((P.J.W.), Southampton, United Kingdom S09 4XY
4. Department of Clinical Biochemistry, King’s College School of Medicine (N.F.T.), Denmark Hill, London, United Kingdom SE5 9RS