Effects of an Abbreviated Obesity Intervention Supported by Mobile Technology: The ENGAGED Randomized Clinical Trial

OBJECTIVE To determine the effects on weight loss of three abbreviated behavioral weight loss interventions with and without coaching and mobile technology. METHODS A randomized controlled efficacy study of three 6-month weight loss treatments was conducted in 96 adults with obesity: 1) self-guided (SELF), 2) standard (STND), or 3) technology-supported (TECH). STND and TECH received eight in-person group treatment sessions. SELF and STND used paper diaries to self-monitor diet, activity, and weight; TECH used a smartphone application with social networking features and wireless accelerometer. RESULTS Weight loss was greater for TECH and STND than SELF at 6 months (-5.7 kg [95% confidence interval: -7.2 to -4.1] vs. -2.7 kg [95% confidence interval: -5.1 to -0.3], P < 0.05) but not 12 months. TECH and STND did not differ except that more STND (59%) than TECH (34%) achieved ≥ 5% weight loss at 6 months (P < 0.05). Self-monitoring adherence was greater in TECH than STND (P < 0.001), greater in both interventions than SELF (P < 0.001), and covaried with weight loss (r(84) = 0.36-0.51, P < 0.001). CONCLUSIONS Abbreviated behavioral counseling can produce clinically meaningful weight loss regardless of whether self-monitoring is performed on paper or smartphone, but long-term superiority over standard of care self-guided treatment is challenging to maintain.