1. Tobacco Research and Treatment Center, Massachusetts General Hospital, Boston, Massachusetts, USA
2. Medical Practice Evaluation Center, Massachusetts General Hospital, Boston, Massachusetts, USA
3. Division of Pulmonary and Critical Care Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
4. Harvard Medical School, Boston, Massachusetts, USA
5. Division of General Internal Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
6. Department of Medicine and Department of Epidemiology and Population Health, Division of Infectious Diseases, Albert Einstein College of Medicine, Bronx, New York, USA
7. Mongan Institute for Health Policy, Massachusetts General Hospital, Boston, Massachusetts, USA