[1] Univ Penn, Dept Family Med & Community Hlth, Ctr Publ Hlth Initiat, Sch Med,Ctr Excellence Canc Commun Res, Philadelphia, PA 19104 USA
[2] Univ Penn, Abramson Comprehens Canc Ctr, Philadelphia, PA 19104 USA
[3] Univ Penn, Predoctoral Program, Sch Med, Philadelphia, PA 19104 USA
[4] Cornell Univ, Dept Commun, Ithaca, NY USA
[5] Univ Penn, Ctr Publ Hlth Initiat, Ctr Clin Epidemiol & Biostat, Philadelphia, PA 19104 USA
[6] Univ Penn, Annenberg Sch Commun, Philadelphia, PA 19104 USA
[7] Univ Penn, Ctr Excellence Canc Commun Res, Philadelphia, PA 19104 USA