1. a Division of General Internal Medicine, and Robert H. Lurie Comprehensive Cancer Center of Northwestern University , Chicago , Illinois , USA
2. b Department of Health Policy , Management & Behavior, University at Albany School of Public Health, Albany , New York , USA
3. c Harvard School of Public Health and Dana Farber Cancer Institute , Boston , Massachusetts , USA
4. d Health Communication and Informatics Research Branch , National Cancer Institute , Bethesda , Maryland , USA
5. e Outcomes Research Branch, National Cancer Institute , Bethesda , Maryland , USA