1. Boston University School of Medicine, Boston, Massachusetts, and University of Erlangen-Nuremberg; Erlangen Germany
2. University of Arizona College of Medicine, Tucson, and University of Pittsburgh Graduate School of Public Health; Pittsburgh Pennsylvania
3. University of Pittsburgh Graduate School of Public Health; Pittsburgh Pennsylvania
4. Royal North Shore Hospital, Institute of Bone and Joint Research, Kolling Institute of Medical Research, and University of Sydney; St. Leonards New South Wales Australia
5. Paracelsus Medical University, Salzburg, Austria, and Chondrometrics GmbH; Ainring Germany
6. Boston University School of Medicine; Boston Massachusetts