*Department of Physical Therapy, University of Alberta, Edmonton, Canada, the University of Washington, Seattle
†Department of Public Health, University of Helsinki, Finland, the University of Washington, Seattle
‡Department of Health Sciences, University of Jyväskylä, Jyväskylä, Finland, the University of Washington, Seattle
§Department of Orthopaedics, University of Washington, Seattle, Washington, the University of Washington, Seattle
¶Department of Radiology, University of Kuopio, Kuopio, Finland, the University of Washington, Seattle
#Southwest Orthopedic Istitute, Dallas, Texas, University of Washington, Seattle
∥Department of Biostatistics, University of Washington, Seattle
