Groen W, van der Net J, Bos K, Abad A, Bergstrom BM, Blanchette VS, Feldman BM, Funk S, Helders P, Hilliard P, Manco-Johnson M, Petrini P, Zourikian N, Fischer K. Joint health and functional ability in children with haemophilia who receive intensive replacement therapy. Haemophilia. 2011 Sep; 17(5):783-90.