Piloting a Reinforcement Learning Tool for Individually Tailoring Just-in-time Adaptive Interventions

NCT05751993 | Completed

• 2 other identifiers: 22-0149R21CA260092
• Study Type: interventional
• Target: 19
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this pilot study is to conduct a 12-week pilot feasibility study testing usability of a reinforcement learning model (AdaptRL) in a weight loss intervention (ADAPT study). Building upon a previous just-in-time adaptive intervention (JITAI), a reinforcement learning model will generate decision rules unique to each individual that are intended to improve the tailoring of brief intervention messages (e.g., what behavior to message about, what behavior change techniques to include), improve achievement of daily behavioral goals, and improve weight loss in a sample of 20 adults.

Conditions

Overweight and Obesity; Overweight; Obesity

Keywords

cancer; risk factor; just-in-time adaptive intervention (JITAI)

Outcome Measures

Primary Outcomes (3)

• Feasibility (success of using the AdaptRL model)

  Feasibility as the success of using the AdaptRL model will be defined as the mean number of messages delivered per participant per day.

  up to 12 weeks

• Study engagement

  Study engagement will be defined as the percent of person-days in which participants accessed the web app.

  up to 12 weeks

• Self-monitoring adherence

  Self-monitoring adherence will be defined as the percent of person-days in which participants tracked at least one weight loss behavior (tracked calories, wore tracker, or self-weighed).

  up to 12 weeks

Secondary Outcomes (12)

• Percent weight loss

  12 weeks

• Moderate-to-vigorous physical activity

  Baseline, 12 weeks

• Dietary intake

  Baseline, 12 weeks

• Adherence to calorie goal

  up to 12 weeks

• Adherence to daily active minutes goal

  up to 12 weeks

Study Arms (1)

ADAPT intervention

EXPERIMENTAL

Participants will receive a smart scale and a physical activity tracker and will have three daily goals: weigh daily, a daily personalized active minutes goal, and a daily calorie goal. For 12 weeks, participants will receive 0-3 text messages per day about their behaviors and progress towards their goals, along with weekly personalized feedback, progress graphs, and lessons and resources available on the website.

Behavioral: ADAPT

Interventions

ADAPT BEHAVIORAL

The intervention is testing the feasibility of a reinforcement learning model to pull in participants' behavioral data (calories, activity, and weight) and use this data along with participants' past behavioral goal achievements to deliver the type of message that should be most effective for a given participant at a given time. At each decision point (morning, midday, and evening on a daily basis), the system evaluates which behaviors a participant is eligible to receive a message about (eating, activity, self-weighing), which intervention options a participant is eligible to receive, and then chooses what type of behavioral message a participant should receive. Over time, the model uses participant data and response to interventions to better tailor message choice.

ADAPT intervention

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18-55 years
• Body Mass Index of 25-40 kg/m2
• English-speaking and writing
• Has a smartphone with a data and text messaging plan

You may not qualify if:

• 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 SSRIs for 3 months)
• Previous surgical procedure for weight loss or planned weight loss surgery in the next year
• Currently pregnant or planning pregnancy in the next 4 months
• Lost 10 or more pounds and kept it off in the last 6 months
• 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). Individuals endorsing joint problems, prescription medication usage, or other medical conditions that could limit exercise will be required to obtain written physician consent to participate
• Pre-existing medical condition(s) that preclude adherence to an unsupervised exercise program, diabetes treated with insulin, history of heart attack or stroke, current treatment for cancer, or inability to walk for exercise
• Type 1 diabetes or currently receiving medical treatment for Type 2 diabetes
• 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
• Health or psychological diagnoses that preclude participation in a prescribed dietary and exercise program, including history of or diagnosis of schizophrenia or bipolar disorder, hospitalization for a psychiatric diagnosis in the past year, a current diagnosis of alcohol or substance abuse
• Report a past diagnosis of or receiving treatment for a DSM-5-TR eating disorder (anorexia nervosa, bulimia nervosa, or other diagnosis)
• Another member of the household is a participant or staff member in this trial
• Not willing to attend one study visit
• Not willing to wear a Fitbit every day
• Reason to suspect that the participant would not adhere to the study intervention

Sponsors & Collaborators

• UNC Lineberger Comprehensive Cancer Center: lead
• RTI International: collaborator
• National Cancer Institute (NCI): collaborator

Study Sites (1)

University of North Carolina at Chapel Hill

Chapel Hill, North Carolina, 27514, United States

Location

Related Links

• University of North Carolina Lineberger Comprehensive Cancer Center Clinical Trials

MeSH Terms

Conditions

Overweight; Obesity; Neoplasms

Condition Hierarchy (Ancestors)

Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Brooke Nezami, PhD, MA

  University of North Carolina, Chapel Hill

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: HEALTH SERVICES RESEARCH
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 20, 2023
• First Posted: March 2, 2023
• Study Start: April 12, 2025
• Primary Completion: August 3, 2025
• Study Completion: August 18, 2025
• Last Updated: August 24, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)