1. Human Engineering Research Laboratories, VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania, USA
2. Department of Rehabilitation Science and Technology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
3. Department of Occupational Therapy, School of Health Professions, The University of Texas Medical Branch, Galveston, Texas, USA
4. Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
5. Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
6. Department of Medicine, Dell Medical School, The University of Texas, Austin, Texas, USA
7. Department of Medicine, South Texas Veterans Health Care System, San Antonio, Texas, USA
8. Department of Physical Therapy, University of Pittsburgh, Pittsburgh, Pennsylvania, USA