1. Stanford University School of Medicine; Center for Education and Research in Family and Community Medicine; Division of General Medical Disciplines; Department of Medicine; Stanford CA USA
2. SRI International; Center for Health Sciences; Menlo Park CA USA
3. Alpert Medical School of Brown University; Department of Family Medicine; Pawtucket RI USA
4. University of California, San Diego; Division of Behavioral Medicine; Department of Family and Preventive Medicine; La Jolla CA USA
5. Keck School of Medicine of University of Southern California; Department of Preventive Medicine; Los Angeles CA USA
6. Providence VA Medical Center; Providence RI USA
7. University of Bristol; Department of Experimental Psychology; Bristol UK
8. University of California, San Francisco (UCSF); Division of Clinical Pharmacology; Departments of Medicine and Bioengineering and Therapeutic Sciences; San Francisco CA USA
9. University of Toronto; Departments of Psychiatry, Pharmacology and Toxicology; Centre for Addiction and Mental Health; Toronto ON Canada
10. Alpert Medical School of Brown University; Department of Psychiatry and Human Behavior; Providence RI USA
11. Perelman School of Medicine; University of Pennsylvania; Department of Psychiatry; Philadelphia PA USA
12. American Legacy Foundation; Schroeder Center for Tobacco and Policy Studies; Johns Hopkins Bloomberg School of Public Health; Department of Health, Behavior and Society; Baltimore MD USA