[1] Imperial Coll London, Sect Invest Med, Hammersmith Hospiwith Testicular Volume Rarelytal, London, England
[2] Univ Edinburgh, MRC Ctr Reprod Hlth, Div Reprod & Dev Sci, Edinburgh, Midlothian, Scotland
[3] City Univ London, Sch Hlth Sci, London, England
[4] Leeds Teaching Hosp NHS Trust, Specialist Lab Med, Leeds, W Yorkshire, England
[5] Univ Hosp Birmingham NHS Fdn Trust, Wolfson EQA Lab, Birmingham, W Midlands, England
[6] Univ Hosp Birmingham NHS Fdn Trust, UK NEQAS, Birmingham, W Midlands, England
[7] Univ Sunderland, Sch Med, Sunderland, Tyne & Wear, England
[8] Newcastle Upon Tyne Hosp NHS Fdn Trust, Newcastle Upon Tyne, Tyne & Wear, England
[9] Univ Coll London Hosp NHS Fdn Trust, Dept Urooncol, London, England
[10] Imperial Coll Healthcare NHS Trust, Imperial Ctr Androl, London, England
[11] Univ Manchester, Dept Med, Manchester, Lancs, England
[12] Univ Oxford, Oxford Ctr Diabet Endocrinol & Metab, Oxford, England
[13] Newcastle Univ, Translat & Clin Res Inst, Newcastle Upon Tyne, Tyne & Wear, England