Background: We assessed the efficacy of the two-year SMART intervention, a digitally delivered, multi-modal weight loss program, on change in self-reported health behaviors and psychosocial measures .
Methods: In total, 404 overweight obese university students and staff(aged 18–35 years) from three colleges in San Diego, CA, USA were enrolled. Participants were randomly assigned (1:1) to either the SMART weight loss intervention (n=202) or general information via website and email (n=202). Self-reported health behaviors and psychosocial measures were assessed every six months for the two-year study period. Between group differences were evaluated using linear mixed effects regression within an intention-to-treat framework. To assess the potential effect of missing data on all the outcomes of interest, a sensitivity analysis was done using multiple imputation. The trial is registered with ClinicalTrials.gov, number NCT01200459.
Results: There were statistically significant differences in self-reported use of the number of strategies for weight management (6.76 [95% CI 2.02 to 11.40], p=0.001) adjusted for sex, ethnicity, and college in the SMART intervention group compared with the control group at 24 months. There were no other differences in self-reported health behavior and psychosocial outcomes observed at the end of the 2-year study period.
Conclusion: A 2-year intervention that delivered theory- and evidence-based weight loss content delivered via Facebook, mobile apps, SMS, and the internet was effective at changing self-reported utilization of strategies of weight management, but not other health behaviors and psychosocial outcomes hypothesized to be important for weight loss.