Ameliorating social isolation: identifying factors that impede or facilitate health-related social behavior change

The Keep Social randomized control trial (RCT) is a 6-week, online study which will test whether, relative to a placebo control condition, an intervention that encourages high-quality in-person social interactions with strangers and acquaintances reduces young adults' (ages 18 - 29) social isolation and loneliness. Participants will complete our 6-week protocol, which includes 6 weeks of passive ecological behavior sampling (i.e., geotracking) and Day Reports, our 4-week Invibe social media messages, plus recurrent Biweekly Assessments (BW1-BW4) that include both self-reported and behavioral measures. The first Monday following enrollment, participants complete the BW1 baseline survey to assess demographic characteristics and initial levels of all outcome variables (primary and secondary, \~20 min). They also (optionally) activate passive geotracking on this day and leave it activated, continuously, for the duration of the study. During the 2-week baseline and 4-week Invibe phases, time-varying psychological and behavioral mediators and moderators will be assessed three times per week via Day Reports. To increase ecological validity, each week, two weekdays (i.e., Monday, Tuesday, Wednesday, or Thursday), and one weekend day (i.e., Friday, Saturday or Sunday) will be randomly selected. Day reports will not be assigned on Mondays if there is a biweekly assessment scheduled.