Texting Motivational Interviewing: A Randomized Controlled Trial of Motivational Interviewing Text Messages Designed to Augment Childhood Obesity Treatment

Text messages improve health outcomes for adults engaged in weight management. Little is known about whether text messaging parents of children enrolled in obesity treatment will improve child health.We conducted a 2-group randomized controlled study among 101 children aged 5-12 and their parent/guardian enrolling in tertiary-care obesity treatment. Participants were randomized to standard care or standard care plus daily motivational interviewing-based text messages. The primary outcome was change in child BMI at 3 months. Secondary outcomes included feasibility, health behaviors, attrition, motivation, and parent BMI.We enrolled 101 parent-child dyads and retained 81% to 3-month follow-up. Child participants had a mean age of 9.9 years, and baseline BMI of 30.5 kg/m2. Half (48%) of participants were Black, and 64% of parent participants had a high school equivalent education or less. Ninety-nine percent of parents owned a mobile device with unlimited text messaging. Parents responded to 80% of texts, and 95% felt the texts "always" or "almost always" helped them make a good health decision. We observed no between-group difference in child zBMI from baseline to 3 months (0.0 vs. 0.2, p = 0.2). Intervention participants had significantly better adherence to clinic visits (3.3 visits vs. 2.1 visits/3 months, p < 0.001).Parent-directed text messages did not significantly change child BMI. However, texting significantly reduced attrition for treatment visits. Nearly all parents in this racially diverse, low-income sample engaged in daily text messaging, making this a feasible approach.