1. 1Collaborative for Research on Outcomes and –Metrics, Georgetown University, Washington, DC
2. 2Department of Neurology, Biostatistics, Bioinformatics & Biomathematics, Georgetown University Medical Center, Washington, DC
3. 3Department of Rehabilitation Medicine, Georgetown University Medical Center, Washington, DC
4. 4MedStar National Rehabilitation Hospital, Washington, DC
5. 5MedStar Health Research Institute, Hyattsville, MD