Self-monitoring (of weight, intake, and activity) is a core component in evidence-based lifestyle interventions for obesity. Research has shown that interventionist feedback increases adherence to self-monitoring and improves weight loss outcomes; however, little empirical evidence exists on how this feedback should be provided. This research study aims to optimize the provision of self-monitoring feedback.

Self-monitoring (e.g., of weight, dietary intake, and physical activity) is a core component in evidence-based comprehensive lifestyle interventions for obesity, and greater adherence to self-monitoring has been associated both with better short-term weight loss and long-term weight loss maintenance. Importantly, research has demonstrated that the provision of interventionist feedback on self-monitoring increases adherence to self-monitoring and improves weight loss outcomes. Little empirical evidence exists, however, to provide guidance on how this feedback should be provided. One study conducted in this area demonstrated that intentions to self-monitor differ by feedback complexity, such that too little (and, conversely, too much) feedback reduces future intentions to self-monitor and engage in related health behavior change; however, less is known regarding how the type and complexity of feedback messages affect actual self-monitoring behavior and subsequent weight loss outcomes. Importantly, provision of this feedback also represents a substantial investment of clinician time; research demonstrated that feedback messages incorporating self-monitoring data related to weight, dietary intake, and physical activity can take ~26 minutes per person to compose. Thus, the investigators propose a line of research that aims to optimize the provision of self-monitoring feedback (i.e., identifying the optimal number and type of feedback messages) for supporting adherence to weight-management behaviors. For the current study, the investigators propose to assess the feasibility and acceptability of a micro-randomized, factorial trial design that will ultimately be used (in a future, fully-powered trial) evaluate the proximal impact of different types and amount of feedback on change in weight and weight-related behaviors (e.g., adherence to self-monitoring, caloric goal attainment, physical activity goal attainment). Using a 2x2x2x2 factorial model, participants will be randomized each week for 16 weeks to one of 16 possible feedback conditions, allowing us to efficiently test four feedback components (i.e., feedback on calorie goal attainment, dietary quality, physical activity goal attainment, or on goal setting) in one study.

Inclusion Criteria:

• Age ≥ 18 years
• BMI ≥ 30.0 kg/m2
• ≤ 175 kg (due to scale limit)
• Own a smartphone (Apple iPhone running iOS 15 or higher or Android smartphone running Android 10 or higher) with a cellular and data plan

Exclusion Criteria:

• Weight > 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
• Currently participating in a weight-loss program
• Weight loss of ≥ 10 lbs in the 6 months prior to initial pre-screening
• Physical limitations that prevent walking 1/4 mile without stopping
• Use of a pacemaker or other implanted medical device
• Currently pregnant
• Currently breastfeeding
• Less than 1-year post-partum
• Plans to become pregnant within the study period
• Lack of written approval for participation from potential participant's physician if the participant has been diagnosed with diabetes, hypertension, or has a history of coronary heart disease
• One or more study participants living in the household (enrollment limited to one participant per household)
• Medical conditions that contraindicate weight loss or prevent completion of the study (e.g., current diagnosis of cancer or terminal illness, dementia, etc.)
• Self-reported eating disorder within past 5 years
• Unable to complete the 17-week study (due to plans to relocate during the study period, etc.)
• Unable or unwilling to provide informed consent
• Unable to read English at the 5th grade level
• Unwilling to accept random assignment
• Unable or unwilling to download the study smartphone applications, wear the physical activity monitor, or use the study e-scale
• Failure to complete baseline assessment measures
• Failure to complete at least 5 out of 7 days of self-monitoring dietary and weight self-monitoring during the behavioral run-in period
• Other conditions which in the opinion of the Principal Investigator would adversely affect participation in the study

De-identified data will be shared upon request following the establishment of an appropriate data use agreement.

The proposed study is a pilot for a larger trial; we will share data from the pilot within one year of completion of the larger trial.