[1] Univ Penn, Leonard Davis Inst Hlth Econ, Div Pulm & Crit Care Med, Philadelphia, PA 19104 USA
[2] Univ Penn, Comprehens Smoking Treatment Program, 51 North 39th St,Suite 251 Wright Saunders Bldg, Philadelphia, PA 19104 USA
[3] Univ Penn, Ctr Interdisciplinary Res Nicotine Addict, Dept Psychiat, Philadelphia, PA 19104 USA
[4] Univ Penn, Abramson Canc Ctr, Philadelphia, PA 19104 USA
[5] Philadelphia Dept Publ Hlth, Philadelphia, PA USA