[1] Free Univ Brussels, Akad Ziekenhuis, Dept Orthopaed & Traumatol, B-1090 Brussels, Belgium
[2] Free Univ Brussels, Akad Ziekenhuis, Dept Internal Med, B-1090 Brussels, Belgium
[3] Ctr Res Epidemiol & Hlth Informat Syst Luxemburg, L-1471 Luxembourg, Luxembourg
[4] McMaster Univ, Dept Obstet & Gynecol, Hamilton, ON L8N 3Z5, Canada
[5] Katholieke Univ Leuven, Ctr Metab Bone Dis, Div Endocrinol, B-3000 Louvain, Belgium
[6] Katholieke Univ Leuven, Ctr Metab Bone Dis, Div Geriatr Med, B-3000 Louvain, Belgium