Just-in-time Adaptive Intervention Messaging in a Digital Weight Loss Intervention for Young Adults
- Conditions
- ObesityOverweightOverweight and Obesity
- Interventions
- Behavioral: Core Behavioral Weight Loss (BWL) InterventionBehavioral: Behavior Change Technique 3 Message (Feedback on Outcome of Behavior)Behavioral: Behavior Change Technique 4 Message (Social Support)Behavioral: Behavior Change Technique 7 Message (Focus on Past Success)Behavioral: Behavior Change Technique 1 Message (Action Planning)Behavioral: Behavior Change Technique 2 Message (Discrepancy between Current Behavior and Goal)Behavioral: Behavior Change Technique 5 Message (Social Comparison)Behavioral: Behavior Change Technique 6 Message (Social Reward)
- Registration Number
- NCT05625061
- Lead Sponsor
- University of North Carolina, Chapel Hill
- Brief Summary
The purpose of this micro-randomized trial is to evaluate the effects of 7 types of intervention messages targeting specific behavior change techniques (i.e., BCT messages) delivered in "just-in-time" (JIT) moments on daily achievement of weight-related behavioral goals among n=201 young adults with overweight and obesity, participating in a digital, mobile comprehensive lifestyle intervention. "Just-in-time adaptive interventions" (JITAIs) are an alternative to the "one size fits all" approach of mobile intervention development that can provide tailored, real-time messaging and support for young adults.
- Detailed Description
An estimated 1 in 2 US adults will have obesity by 2030, which is a major cause of morbidity and mortality. The highest risk of weight gain is among young adults ages 18-35 years. In-person behavioral interventions generally produce clinically significant weight losses, but cost and reduced reach limit their ability to impact obesity at a population level. Web-based interventions that mimic the structure of weekly face-to-face treatment have proven a viable alternative, though weight losses are generally smaller than in-person treatment. Mobile treatments have the potential for high reach, but have been less effective, producing 1-3 kgs over 6 months. Newer digital intervention approaches called "just-in-time adaptive interventions" (JITAIs) promise to improve upon mobile outcomes by offering adaptive, personalized feedback on behavior, which consists of providing the "right type of support" at "the right time" rather than on a fixed schedule. This "just-in- time," or JIT, approach is made possible by the emergence of low-cost and widely available digital health tools that allow for the collection of continually updated health data. However, to date, no JITAIs have successfully targeted multiple weight-related behaviors (weighing, activity, and diet), and there has been no systematic examination of what types of messaging interventions best promote adherence to these three weight loss behaviors, for whom they are effective, and under what conditions. To address this problem, a micro-randomized trial will be used to evaluate the effects of 7 types of intervention messages targeting specific behavior change techniques (i.e., BCT messages) delivered in JIT moments on daily achievement of behavioral goals among n=201 young adults with overweight and obesity. All participants will receive a 6-month behavioral weight loss intervention using our Nudge mobile app, which includes evidence-based weekly lessons, tailored feedback, self-monitoring, and daily BCT messages. Participants will receive a wireless scale, activity tracker, and track "red" foods (high-calorie foods) in the app and have 3 goals: weigh daily, a daily active minutes goal that gradually increases if met, and a daily red foods limit. At 3 decision points per day, participants will be micro-randomized to receive or not receive 1 of 7 types of BCT messages. Each intervention message has unique decision rules for availability. Candidate intervention message options have been carefully selected from empirical evidence, tested in our prior studies, or are from our pilot micro-randomized trial. Assessments will occur daily, and at 0, 3 and 6 months, to accomplish the following specific aims: 1) Evaluate the effects of each behavior change technique message (i.e., BCT message) on daily adherence to weight loss behaviors; 2) Determine whether the effects of BCT messages on proximal outcomes change over time; and 3) Assess whether the effects of BCT messages on proximal outcomes are moderated by participants' contextual factors. Findings will guide how adaptive, behaviorally- and contextually-dependent messages are incorporated into future JITAIs for weight loss.
Recruitment & Eligibility
- Status
- ACTIVE_NOT_RECRUITING
- Sex
- All
- Target Recruitment
- 206
- Body mass index (BMI) of 25 - 45 kg/m^2 at baseline
- English-speaking, reading, and writing
- Own a smartphone with a data and text messaging plan
- Type 1 diabetes or currently receiving medical treatment for Type 2 diabetes
- Report a heart condition, chest pain during periods of activity or rest, or loss of consciousness on the Physical Activity Readiness Questionnaire (PAR-Q; items 1-4).
- Other health problems which may influence the ability to walk for physical activity or be associated with unintentional weight change, including cancer treatment within the past 5 years or tuberculosis
- Lost 10 lbs. or more of body weight (and kept it off) in the last 3 months
- Past diagnosis of or receiving treatment for a clinically diagnosed eating disorder (anorexia nervosa or bulimia nervosa)
- Current symptoms of alcohol or substance dependence
- Currently pregnant, pregnant within the past 6 months, or planning to become pregnant within the next 6 months
- Untreated thyroid disease or any changes (type or dose) in thyroid medication in last 6 months
- Hospitalization for depression or other psychiatric disorder within the past 12 months
- History of psychotic disorder or bipolar disorder
- Currently participating in a weight loss, nutrition, or physical activity study or program or other study that would interfere with this study
- Currently using prescription medications with known effects on appetite or weight (e.g., oral steroids, weight loss medications), with the exception of individuals on a stable dose of Selective Serotonin Reuptake Inhibitors (SSRIs) for 3 months)
- Previous surgical procedure for weight loss or planned weight loss surgery in the next year
- Another member of the household is a participant or staff member on this trial
- Reason to suspect that the participant would not adhere to the study intervention
- Reside outside of the United States
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SEQUENTIAL
- Arm && Interventions
Group Intervention Description Core Behavioral Weight Loss (BWL) Intervention Core Behavioral Weight Loss (BWL) Intervention Behavioral weight loss core intervention, includes activity tracker, wireless scale, daily self-weighing, and smartphone app with weekly behavioral lessons, food tracking log, weekly tailored feedback summary, and daily weight-related behavioral goals. Core intervention component is combined with each of the 7 intervention messages to be tested repeatedly over time. Core BWL Intervention + BCT 3 Message (Feedback on Outcome of Behavior) Behavior Change Technique 3 Message (Feedback on Outcome of Behavior) Core BWL Intervention + Message testing the Behavior Change Technique "Feedback on Outcome of Behavior" Core BWL Intervention + BCT 4 Message (Social Support) Behavior Change Technique 4 Message (Social Support) Core BWL Intervention + Message testing the Behavior Change Technique "Social Support" Core BWL Intervention + BCT 7 Message (Focus on Past Success) Behavior Change Technique 7 Message (Focus on Past Success) Core BWL Intervention + Message testing the Behavior Change Technique "Focus on Past Success" Core BWL Intervention + BCT 1 Message (Action Planning) Behavior Change Technique 1 Message (Action Planning) Core BWL Intervention + Message testing the Behavior Change Technique "Action Planning" Core BWL Intervention + BCT 2 Message (Discrepancy) Behavior Change Technique 2 Message (Discrepancy between Current Behavior and Goal) Core BWL Intervention + Message testing the Behavior Change Technique "Discrepancy Between Current Behavior and Goal" Core BWL Intervention + BCT 5 Message (Social Comparison) Behavior Change Technique 5 Message (Social Comparison) Core BWL Intervention + Message testing the Behavior Change Technique "Social Comparison" Core BWL Intervention + BCT 6 Message (Social Reward) Behavior Change Technique 6 Message (Social Reward) Core BWL Intervention + Message testing the Behavior Change Technique "Social Reward"
- Primary Outcome Measures
Name Time Method Met daily weighing goal Daily throughout the study, a total of up to 24 weeks Wireless scales will be used to collect daily weight measurements, which are transmitted directly to the study app servers in real time. Participants are instructed to weigh each day. On the day of randomization, a dichotomous outcome of whether a participant weighed or did not weigh is assessed.
At or under daily red foods limit Daily throughout the study, a total of up to 24 weeks Participants will record red foods in the study app; data sync with study servers in real time from the participants' app. On the day of randomization, a dichotomous outcome of whether a participant stayed at or under their red foods limit or not is assessed. Days without complete red food tracking are counted as not meeting the red foods limit.
Met daily active minutes goal Daily throughout the study, a total of up to 24 weeks Activity trackers will be used to collect daily active minutes, which are minutes of moderate-to-vigorous intensity physical activity accumulated in bouts of at least 10 minutes. On the day of randomization, a dichotomous outcome of whether a participant met or exceeded their daily active minutes goal or not is assessed. Days with no tracker wear are counted as not meeting the goal.
- Secondary Outcome Measures
Name Time Method Proportion of daily active minutes goal met Daily throughout the study, a total of up to 24 weeks Calculation of the proportion of daily active minutes goal met using activity tracker data.
Met daily weighing goal tomorrow Daily throughout the study, a total of up to 24 weeks Wireless scales will be used to collect daily weight measurements, which are transmitted directly to the study app servers in real time. Participants are instructed to weigh each day. On the day after randomization, a dichotomous outcome of whether a participant weighed or did not weigh is assessed.
Met daily active minutes goal tomorrow Daily throughout the study, a total of up to 24 weeks Activity trackers will be used to collect daily active minutes, which are minutes of moderate-to-vigorous intensity physical activity accumulated in bouts of at least 10 minutes. On the day after randomization, a dichotomous outcome of whether a participant met or exceeded their daily active minutes goal or not is assessed. (Days with no tracker wear are counted as not meeting the goal).
At or under daily red foods limit tomorrow Daily throughout the study, a total of up to 24 weeks Participants will record red foods in the study app; data sync with study servers in real time from the participants' app. On the day after randomization, a dichotomous outcome of whether a participant stayed at or under their red foods limit or not is assessed. Days without complete red food tracking are counted as not meeting the red foods limit.
Proportion of daily red foods limit Daily throughout the study, a total of up to 24 weeks Calculation of the proportion of the daily red foods limit recorded in the study app.
Number of active minutes Daily throughout the study, a total of up to 24 weeks Total number of active minutes on the day of message randomization (at the participant-day level) across the 6 month study.
Weight change Baseline, 6 months Absolute weight change (kg) from baseline to 6 months. Weight will be objectively measured on a digital scale in the participant's home.
Percent weight change Baseline, 6 months Change in weight (%) from baseline to 6 months. Weight will be objectively measured on a digital scale in the participant's home. Percent weight change at 6 months is calculated as ((weight (kg) at 6 months - weight (kg) at baseline)/(weight (kg) at baseline))\*100
Proportion of days met daily weighing goal Daily throughout the study, a total of up to 24 weeks Calculation of the proportion of study days weighed.
Number of red foods Daily throughout the study, a total of up to 24 weeks Total number of red foods on the day of message randomization (at the participant-day level) across the 6 month study.
Trial Locations
- Locations (1)
University of North Carolina at Chapel Hill
🇺🇸Chapel Hill, North Carolina, United States