1. Medical Research Council Environmental Epidemiology Unit, University of Southampton (D.I.W.P., D.J.P.B., C.H.D.F, C.B.W.), Southampton, United Kingdom
2. the Department of Medicine, University of Edinburgh, Western General Hospital (J.R.S., B.R.W.), Edinburgh, Scotland
3. the Regional Endocrine Unit, Southampton General Hospital (P.W.), Southampton, United Kingdom