1. Department of Family Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC.
2. Program on Integrative Medicine, Department of Physical Medicine and Rehabilitation, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC.
3. Department of Biostatistics, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC.
4. Community and Family Medicine, Duke Center for Clinical Health Policy Research, Duke University, Durham, NC.
5. Private practice, Carrboro, NC.
6. Department of Neurology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC.