[1] Guys Kings Coll & St Thomass, Sch Biomed Sci, Div Anat Cell & Human Biol, London SE1 9RT, England
[2] N Hampshire Hosp, Dept Surg, Basingstoke, Hants, England
[3] Chelsea & Westminster Hosp, Dept Surg, London, England
[4] Joyce Green Hosp, Dept Surg, Dartford, England
[5] Macclesfield Hosp, Dept Surg, Macclesfield, Cheshire, England
[6] Stepping Hill Hosp, Stockport, England
[7] Colchester Dist Gen Hosp, Dept Surg, Colchester, Essex, England
[8] City Univ London, Sch Social Sci, London EC1V 0HB, England
[9] Univ Oxford, Inst Hlth Sci, Oxford Hlth Econ Grp, Oxford, England
[10] St Bartholomews Hosp, Fertil Ctr, London, England
[11] So Gen Hosp NHS Trust, Dept Gynecol, Glasgow, Lanark, Scotland
[12] Natl Hlth Serv Scotland, Informat & Stat Div, Edinburgh, Midlothian, Scotland
[13] Strategan Dis & Therapy Management, Basingstoke, Hants, England