Charge: A Text Messaging-based Weight Loss Intervention

Not Applicable

Completed

Brief Summary: This study evaluates different versions of a text messaging-based app for weight loss. This study will place participants to 1 of 32 experimental conditions that reflect different texting components and levels. Participants will be randomized to a condition. The investigators will recruit 448 adults into a 6-month weight loss program, with an additional follow-up 6-months after the intervention ends.

Detailed Description: Standalone text messaging-based weight loss treatments are scalable and can achieve population reach. However, these interventions are also modular; they can be delivered independently to maximize cost-effectiveness or combined with other approaches (e.g. provider counseling) to maximize outcomes. This study is a 12-month experimental trial among 448 adults with obesity. All participants will receive a core 6-month weight loss texting intervention that includes tailored behavior change goals, interactive self-monitoring, automated feedback, and skills training. Participants will be randomly assigned to 1 of 32 different experimental conditions.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

prior or planned bariatric surgery
psychiatric hospitalization in past 12 months
pregnancy, nursing, or planned pregnancy
history of a cardiovascular event
history of an eating disorder
history of a condition (e.g., end stage renal disease, cancer, schizophrenia) or use of medications (e.g., lithium, steroids, anti-psychotics) that would affect weight measurement, for which weight loss is contraindicated, or might promote weight change
current participation in a weight loss trial and/or recent weight loss > 10%
investigator discretion for safety reasons

Primary Outcome Measures

Name	Time	Method
Average Weight Change	baseline, 6 months	Mean change in weight in kg (6 months post-randomization- baseline weight)

Secondary Outcome Measures

Name	Time	Method
Change in Diet	baseline, 6 months	To experimentally determine the effects of text messaging components and levels on change in dietary intake using The Rapid Eating Assessment for Participants - Shortened version (REAP-S). The range of score is 13 to 39, where a higher score indicates more healthy dietary intake.
Average Change in Physical Activity	baseline, 6 months	To experimentally determine the effects of text messaging components and levels on change in weekly minutes of physical activity based on the WHO Global Physical Activity Questionnaire version 2 (GPAC 2). The range of scores is 0 minutes/week to 10,080 minutes/week (maximum number of minutes in a week).