Trial results for a study evaluating "Just-in-time Adaptive Intervention Messaging in a Digital Weight Loss Intervention for Young Adults" in Obesity and Overweight were posted on ClinicalTrials.gov on 2026-01-27. The study found that receiving any intervention message significantly increased the odds of meeting daily weighing goals, with an odds ratio of 1.06 (95% CI 1.01-1.12, p=0.03).
Background
Obesity and overweight are significant public health concerns, contributing to a range of chronic diseases. Effective weight management strategies are crucial, particularly for young adults. Digital health interventions, often delivered via mobile devices, offer a scalable approach to support behavioral changes. "Just-in-time adaptive interventions" (JITAIs) represent an advanced form of digital support, designed to deliver tailored messages and assistance at opportune moments, moving beyond a "one size fits all" approach. This trial investigated whether such real-time, personalized messaging could enhance adherence to weight-related behavioral goals, specifically daily weighing, within a comprehensive digital lifestyle intervention.
Trial design
This completed micro-randomized trial, designated as Phase NA, enrolled 255 participants to evaluate the effects of various intervention messages. The study focused on young adults with Obesity and Overweight. The intervention involved a digital, mobile comprehensive lifestyle program that delivered 7 types of "just-in-time" (JIT) messages targeting specific behavior change techniques (BCTs). The trial's purpose was to assess the impact of these messages on the daily achievement of weight-related behavioral goals.
Key results
The trial results focused on the outcome of "Met Daily Weighing Goal" and the impact of receiving different types of intervention messages:
- Met Daily Weighing Goal (Overall Message Effect):
- Among observations where any message was received, 4399 goals were met.
- Among observations where no message was received, 4167 goals were met.
- Met Daily Weighing Goal (Weighing Message Effect):
- Among observations where a weighing message was received, 1496 goals were met.
- Among observations where a weighing message was not received, 1393 goals were met.
- Met Daily Weighing Goal (Weighing BCT 1 Message - Action Planning Effect):
- Among observations where a Weighing BCT 1 (Action Planning) message was received, 249 goals were met.
- Among observations where a Weighing BCT 1 (Action Planning) message was not received, 226 goals were met.
- Met Daily Weighing Goal (Weighing BCT 2 Message - Discrepancy Effect):
- Among observations where a Weighing BCT 2 (Discrepancy) message was received, 266 goals were met.
- Among observations where a Weighing BCT 2 (Discrepancy) message was not received, 247 goals were met.
- Met Daily Weighing Goal (Weighing BCT 3 Message - Feedback on Outcome of Behavior Effect):
- Among observations where a Weighing BCT 3 (Feedback on Outcome of Behavior) message was received, 268 goals were met.
- Among observations where a Weighing BCT 3 (Feedback on Outcome of Behavior) message was not received, 228 goals were met.
- Met Daily Weighing Goal (Weighing BCT 4 Message - Social Support Effect):
- Among observations where a Weighing BCT 4 (Social Support) message was received, 237 goals were met.
- Among observations where a Weighing BCT 4 (Social Support) message was not received, 264 goals were met.
Key analyses using generalized estimating equations (GEE) with a logit link function revealed the following odds ratios for meeting the daily weighing goal:
- For receiving Any Message compared to not receiving a message: Odds Ratio (OR) of 1.06 (95% CI 1.01-1.12), with a p-value of 0.03.
- For receiving a Weighing Message compared to not receiving this type of message: Odds Ratio (OR) of 1.08 (95% CI 0.99-1.17), with a p-value of 0.07.
- For receiving a Weighing BCT 1 Message (Action Planning) compared to not receiving this type of message: Odds Ratio (OR) of 1.14 (95% CI 0.92-1.41), with a p-value of 0.23.
- For receiving a Weighing BCT 2 Message (Discrepancy) compared to not receiving this type of message: Odds Ratio (OR) of 1.02 (95% CI 0.83-1.25), with a p-value of 0.85.
- For receiving a Weighing BCT 3 Message (Feedback on Outcome of Behavior) compared to not receiving this type of message: Odds Ratio (OR) of 1.17 (95% CI 0.96-1.42), with a p-value of 0.12.
- For receiving a Weighing BCT 4 Message (Social Support) compared to not receiving this type of message: Odds Ratio (OR) of 0.9 (95% CI 0.74-1.09), with a p-value of 0.29.
What this means
The results suggest that the overall strategy of delivering "just-in-time" intervention messages within a digital weight loss program can be effective in promoting adherence to daily weighing goals among young adults with obesity and overweight. The statistically significant odds ratio of 1.06 for receiving any message indicates a modest but meaningful increase in the likelihood of meeting this behavioral goal. While the overall message delivery showed a positive effect, the individual analyses for specific behavior change technique (BCT) messages did not reach statistical significance at the p=0.05 level, though some showed a trend towards increased odds (e.g., Weighing BCT 3 Message with OR 1.17 and p=0.12). Interestingly, the Weighing BCT 4 (Social Support) message showed an odds ratio of 0.9, suggesting it might not have been as effective in this context. These findings highlight the potential of JITAIs to support weight management behaviors and suggest that the cumulative effect of various messages may be more impactful than individual message types for certain behaviors.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT05625061, titled "Just-in-time Adaptive Intervention Messaging in a Digital Weight Loss Intervention for Young Adults", were posted on 2026-01-27 on clinicaltrials.gov.