[1] Univ Manchester, Arthritis Res Campaign Epidemiol Unit, Manchester, Lancs, England
[2] Univ Sheffield, Sch Med & Biomed Sci, Sheffield S10 2JF, S Yorkshire, England
[3] Chapel Allerton Hosp, Acad Unit Musculoskeletal Dis, Leeds LS7 4SA, W Yorkshire, England
[4] Kings Coll Hosp London, Natl Hlth Serv Fdn Trust, London SE5 9RS, England
[5] Univ Aberdeen, Dept Med & Therapeut, Bone Res Grp, Aberdeen AB25 2ZD, Scotland
[6] Univ Oxford, Inst Musculoskeletal Sci, Botnar Res Ctr, Oxford OX3 7LD, England