1. Department of Physical Therapy and Rehabilitation Science, The University of Iowa Roy J and Lucille A Carver College of Medicine , Iowa City, Iowa , USA
2. Physical Therapy Department, St. Ambrose University , Davenport, Iowa , USA
3. The University of Iowa Clinical Trials Statistical and Data Management Center , Iowa City Iowa , USA
4. Department of Biostatistics, The University of Iowa , Iowa City, Iowa , USA
5. Department of Anesthesia, The University of Iowa , Iowa City, Iowa , USA
6. Kepros Physical Therapy , Cedar Rapids, Iowa , USA
7. Vanderbilt University Medical Center, Division of Rheumatology and Immunology , Nashville, Tennessee , USA