Ignite Pilot: Goal Setting in a Digital Weight Loss Intervention

The goal of this pilot trial is to learn about the optimal intensity level of goals in a digital weight loss intervention among adults with overweight or obesity. The main questions of the study are to assess the feasibility and acceptability of different goal intensities across four domains (calorie goal, step goal, eating window goal, red zone food goal). The investigators will recruit 32 total participants to the trial. Recruitment will occur through remote channels. Interested individuals will be directed to an online screening questionnaire; those who are eligible will then be invited to attend an initial remote session with study personnel to ensure interest and eligibility in the study. The weight loss intervention will last 10 weeks, and all participants will receive a "core" treatment consisting of self-monitoring weight, food intake, and steps (all via digital tools provided by the study team), along with behavioral lessons, action plans, and tailored feedback. Depending on which group participants are assigned to in the study, individuals will receive either a more or less challenging goal across the four domains. All study tasks will occur remotely, thus, participants will never come in-person for any tasks. Assessment of body weight and other measures will occur at the beginning of the trial ("baseline"), and at 4 weeks and 10 weeks. The investigators will use the Multiphase Optimization Strategy (MOST) framework to identify which of the goal intensity levels result in meaningful engagement and weight loss. The current study is the first step towards answering this question; it is designed as a pilot factorial trial, which focuses on feasibility and acceptability. In total, there will be 16 treatment conditions.

weight loss, Multiphase Optimization Strategy, behavioral intervention, factorial trial, goal setting, time-restricted eating

This study uses a full factorial experimental design to test the impact of four intervention components, each with two levels (i.e., a 2x2x2x2).

Calorie Goal (easier) + Step Goal (easier) + Eating Window Goal (easier) + Red Zone Food Goal (easier)

Calorie Goal (easier) + Step Goal (easier) + Eating Window Goal (easier) + Red Zone Food Goal (harder)

Calorie Goal (easier) + Step Goal (easier) + Eating Window Goal (harder) + Red Zone Food Goal (easier)

Calorie Goal (easier) + Step Goal (easier) + Eating Window Goal (harder) + Red Zone Food Goal (harder)

Calorie Goal (easier) + Step Goal (harder) + Eating Window Goal (easier) + Red Zone Food Goal (easier)

Calorie Goal (easier) + Step Goal (harder) + Eating Window Goal (easier) + Red Zone Food Goal (harder)

Calorie Goal (easier) + Step Goal (harder) + Eating Window Goal (harder) + Red Zone Food Goal (easier)

Calorie Goal (easier) + Step Goal (harder) + Eating Window Goal (harder) + Red Zone Food Goal (harder)

Calorie Goal (harder) + Step Goal (easier) + Eating Window Goal (easier) + Red Zone Food Goal (easier)

Calorie Goal (harder) + Step Goal (easier) + Eating Window Goal (easier) + Red Zone Food Goal (harder)

Calorie Goal (harder) + Step Goal (easier) + Eating Window Goal (harder) + Red Zone Food Goal (easier)

Calorie Goal (harder) + Step Goal (easier) + Eating Window Goal (harder) + Red Zone Food Goal (harder)

Calorie Goal (harder) + Step Goal (harder) + Eating Window Goal (easier) + Red Zone Food Goal (easier)

Calorie Goal (harder) + Step Goal (harder) + Eating Window Goal (easier) + Red Zone Food Goal (harder)

Calorie Goal (harder) + Step Goal (harder) + Eating Window Goal (harder) + Red Zone Food Goal (easier)

Calorie Goal (harder) + Step Goal (harder) + Eating Window Goal (harder) + Red Zone Food Goal (harder)

All participants will receive a 10-week core behavioral weight loss treatment consisting of: self-monitoring weight, steps, and food intake; behavioral lessons; action plans; and tailored feedback. The intervention will be delivered remotely via email and digital tools (such as a smart scale, Fitbit activity tracker, and Fitbit app).

Participants will receive a more challenging daily eating window goal, akin to time-restricted eating.

average percentage of days in the 10-week intervention of self-monitoring weight (assessed objectively via smart scale); a benchmark of self-monitoring 75% of days would indicate feasibility

average percentage of days in the 10-week intervention of self-monitoring steps (assessed objectively via Fitbit activity tracker); a benchmark of self-monitoring 75% of days would indicate feasibility

average percentage of days in the 10-week intervention of self-monitoring dietary intake (assessed via Fitbit mobile app); a benchmark of self-monitoring 75% of days would indicate feasibility

(Acceptability) Would you recommend the weight loss program to a friend who is trying to lose weight?

the proportion of participants who submitted a weight entry at 10 weeks; a benchmark of 80% would indicate feasibility

the proportion of participants who completed the web survey; a benchmark of 80% would indicate feasibility

average percentage of days in the 10-week intervention of meeting the daily calorie goal (assessed via Fitbit mobile app); a benchmark of 75% of days would indicate feasibility

average percentage of days in the 10-week intervention of meeting the daily step goal (assessed via Fitbit activity tracker); a benchmark of 75% of days would indicate feasibility

average percentage of days in the 10-week intervention of meeting the daily eating window goal (assessed via survey); a benchmark of 75% of days would indicate feasibility

average percentage of weeks in the 10-week intervention of meeting the weekly Red Zone Food goal (assessed via survey); a benchmark of 75% of weeks would indicate feasibility

change in weight from baseline to 10-week (end of intervention); assessed objectively via smart scale

Inclusion Criteria: adults (ages 18+ years) body mass index (BMI) 25.0 to 45.0 kg/m^2 smartphone ownership willingness to install the Fitbit mobile app on their phone access to a personal email account English language proficiency interest in losing weight through behavioral strategies living in the United States Exclusion Criteria: concurrent enrollment in another weight management intervention loss of ≥10 lbs. in the past 6 months current use of a weight loss medication prior or planned bariatric surgery current or planned pregnancy in the trial period currently breastfeeding lives with someone else participating in the study hospitalization for a mental health condition in the past 12 months inability to engage in moderate forms of physical activity akin to brisk walking (assessed by the Physical Activity Readiness Questionnaire) if weight loss is contraindicated or might be impacted by a condition or medication (e.g., end stage renal disease, cancer, schizophrenia, dementia, steroids, anti-psychotics) if an individual would be better suited for a more intensive or different type of intervention based on a health condition (e.g., individuals with history of an eating disorder or cardiovascular event, uncontrolled hypertension, or uncontrolled diabetes mellitus) investigator discretion for safety reasons