1. Center for Medical Decision Making, Department of Public Health, Erasmus Medical Center, Rotterdam, the Netherlands.
2. Department of Neurological Surgery, University of California, San Francisco, San Francisco, California.
3. Brain and Spinal Injury Center, San Francisco General Hospital, San Francisco, California.
4. Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
5. Department of Neurological Surgery, Virginia Commonwealth University, Richmond, Virginia.