[1] Imperial Coll, Dept Metab Digest & Reprod, London, England
[2] Univ Med & Hlth Sci, Royal Coll Surg Ireland RCSI, Dublin, Ireland
[3] Univ Hosp Birmingham NHS Fdn Trust, Birmingham, England
[4] Univ Hosp NHS Fdn Trust, Birmingham Qual UK NEQAS, Birmingham, England
[5] Univ Sheffield, Royal Hallamshire Hosp, Med Sch, Dept Biochem, Sheffield, England
[6] Walsall Manor Hosp, Dept Clin Biochem, Black Country Pathol Serv, Walsall, England
[7] Univ Wolverhampton, Fac Sci & Engn, Sch Med & Clin Practice, Wolverhampton, England
[8] Bristol Royal Infirm & Gen Hosp, Dept Clin Biochem, Bristol, England
[9] Spire Hosp, Dept Urol, Birmingham, England
[10] Univ Hosp Birmingham NHS Fdn Trust, Dept Clin Biochem, Sutton Coldfield, England
[11] Oxford Ctr Diabet Endocrinol & Metab, Oxford, England
[12] Princess Wales Hosp, Porthcawl Med Ctr, Dept Urol, Bridgend, Wales
[13] Royal Victoria Infirm, Dept Blood Sci, Newcastle Upon Tyne, England
[14] Great Western Hosp NHS Fdn Trust, Swindon, England
[15] Bedfordshire Hosp NHS Fdn Trust, Bedford, Beds, England
[16] Univ Manchester, Fac Biol Med & Hlth, Sch Med Sci, Div Endocrinol Diabet & Gastroenterol, Manchester, England
[17] Newcastle Univ, Newcastle upon Tyne Hosp NHS Fdn Trust & Translat, Clin Res Inst, Dept Endocrinol Diabet & Metab, Newcastle Upon Tyne, England
[18] Hammersmith Hosp, Imperial Coll, Fac Med, Dept Metab Digest & Reprod, 6th Floor Commonwealth Bldg,Du Cane Rd, London W12 0NN, England