About this trial
The purpose of this research study is to learn how to identify the most effective ways to provide weekly feedback on participants' progress toward intervention goals during a weight loss program.
Eligibility criteria
This trial accepts healthy volunteersQualifiers
Age greater than or equal to 18 years
BMI greater than or equal to 25.0 kg/m2
Weight less than or equal to 175 kg (due to scale limit)
Own a smartphone compatible with Fitbit (e.g., an Apple iPhone running iOS 16.4 or higher or Android smartphone running Android 11 or higher) with a cellular and data plan
Disqualifiers
Weight greater than 175 kg (due to a weight limit of the study-provided scale)
Smartphone device owned deemed incompatible with the Fitbit App
History of bariatric surgery or plans to obtain bariatric surgery during the study period
Current use of weight loss medications, or use of weight loss medications in the 6 months prior to initial pre-screening
Trial design
Single group
Treatments tested in this trial
Positive Reinforcement
BehavioralFeedback composed by a study interventionist that focuses exclusively on positively reinforcing the participant's progress toward achieving their goals.
Positive Reinforcement + Areas for Change
BehavioralFeedback provided by a study interventionist that combines positive reinforcement of the participant's progress with constructive guidance on areas for improvement to support successful goal attainment.
Treatment groups
Trial outcomes
Primary outcomes
Weight change
Mixed-effects models will be used to investigate the impact of each feedback condition on our primary outcome of weight change. Fitted model estimates will be used to calculate the slope of weight change from day 1 (the day a feedback message is delivered) through day 7 of each week. Positive slopes indicate weight gain, while negative slopes indicate weight loss.
Secondary outcomes
Frequency of self-monitoring weight
Frequency of self-monitoring weight will be defined as the number of days (0-7) in the week following a feedback message (from day 1, the day that a feedback message is received, to day 7) in which the participant records a valid (non-outlier) e-scale weight.
Frequency of self-monitoring dietary intake
A valid "day" of dietary self-monitoring will be defined as ≥ 800 kcal recorded, consistent with prior research. Frequency is calculated as the number of valid days (0-7) recorded the week after a feedback message is delivered (from day 1, the day that a feedback message is received, to day 7).
Total caloric intake
Total caloric intake will be calculated by summing calories consumed during the week following a feedback message is received (from day 1, the day that a feedback message is received, to day 7)
Calorie goal attainment
Calorie goal attainment for each day during the week after a feedback message is received (from day 1, the day a feedback message is received, to day 7). Calorie goal attainment will be calculated as \[TOTAL KCAL INTAKE FOR THE DAY\] - \[CALORIE GOAL\]. Daily difference scores for the 7 days will be averaged across the week to determine overall adherence to the caloric intake goal.
Sponsors and contacts
Click on the lead sponsor to view all of their trials.
University of Virginia
Lead sponsor
University of Florida
Collaborator
Wake Forest University Health Sciences
Collaborator