1. Department of Psychiatry, Center for Studies of Addiction, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
2. Department of Cardiology, Sheba Medical Center, Sackler School of Medicine, Tel Aviv, Israel
3. Department of Psychiatry, Cambridge Health Alliance, Harvard Medical School, Boston, MA, USA
4. Physician Health Services, Massachusetts Medical Society, Waltham, MA, USA