Gary G Bennett1, Dori M Steinberg2, Sherry L Pagoto3. 1. Duke Global Digital Health Science Center, Duke Global Health Institute, Duke University, Durham, NC; Department of Psychology and Neuroscience, Duke University, Durham, NC. Electronic address: gary.bennett@duke.edu. 2. Duke Global Digital Health Science Center, Duke Global Health Institute, Duke University, Durham, NC. 3. University of Massachusetts Medical School, Worcester.