Sandra D Comer1, Robert H Dworkin2, Eric C Strain3. 1. Columbia University Medical Center, New York State Psychiatric Institute and the Department of Psychiatry, New York. 2. Department of Anesthesiology and Perioperative Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York. 3. Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.