1. From the Clinical Practice Research Unit (CPRU; C.L.W., J.V.W., M.J.L., M.F.A., H.A.D., C.J.S., C.E.L.), Preston, UK; Merseycare National Health Service Trust (C.F.D.), Liverpool, UK; Belfast Trust (C.I.A.J.), Belfast, UK; and St George's Healthcare National Health Service Trust (M.D.v.d.B.), London, UK.