Precision Public Health: Enhancing Connections to Develop Just-in-Time Adaptive Intervention Strategies (Nudge)

November 11, 2019 updated by: University of North Carolina, Chapel Hill
The purpose of this pilot study is to examine the effects of different types of just-in-time intervention messages on daily meeting dietary, activity, and weighing goals in a sample of young adults participating in a mobile-based weight loss program.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Public health interventions typically rely on a set schedule of intervention delivery. Advances in technology and computer tailoring allow us to go from a "one size fits all" approach to one that uses digital health data to deliver "just-in-time adaptive interventions," or JITAIs, that can vary the timing, dose, and content of intervention messages to individuals. This pilot study is a micro-randomized trial that evaluates the effects of various intervention message options delivered in JIT moments on meeting dietary, activity, and weighing goals among young adults in a mobile-based weight loss program.

The Nudge study is a 12-week mobile health weight loss program delivered via a native smartphone application. Individuals are asked to track their red foods (high-calorie, high-fat foods) in the app daily and meet their personalized red foods goal, wear a Fitbit daily and meet their daily active minutes goal, and weigh daily on their WiFi-enabled scale. Up to 4 times each day, participants are randomized to receive or not receive intervention messages in order to examine the effects of these intervention message types on meeting daily weighing goals, red food goals, and activity goals. This is a within-subjects design in which each participant serves as their own control, and data is analyzed at the person-day level.

Study Type

Interventional

Enrollment (Actual)

53

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • North Carolina
      • Chapel Hill, North Carolina, United States, 27599
        • Department of Health Behavior, University of North Carolina, Chapel Hill

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 35 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Age 18-35
  • BMI of 25-40 kg/m²
  • Not adhering to the US physical activity guidelines of at least 150 moderate-to-vigorous intensity activity minutes/week
  • English-speaking and writing
  • No 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
  • Has an iPhone with iOS 11 (or willing to download it) with internet access and text messaging plan
  • Has home wireless access compatible with Fitbit Aria 2 scale (802.11b/g/n)

Exclusion Criteria:

  • Current participation in another physical activity or weight control program
  • Currently pregnant, pregnant in last 6 months, or planning pregnancy in next 3 months
  • Report a heart condition, chest pain during periods of activity or rest, loss of consciousness, joint or bone problems, or prescription medicine usage for blood pressure or heart condition on the Physical Activity Readiness Questionnaire (PAR-Q)
  • Health or psychological diagnoses that preclude participation in a prescribed dietary and exercise program, including diagnosis of schizophrenia or bipolar disorder, hospitalization for a psychiatric diagnosis in the past year, diagnosis of alcohol or substance abuse
  • Occupation requires primarily night shift work
  • Owns and uses a physical activity tracker
  • Moving out of area in next 4 months
  • Out of town for a week or more during study period
  • Not willing to attend two study visits

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Nudge Intervention

Each of 7 intervention message options has specific decision rules (including weighed/not weighed and progress toward daily dietary and activity goals) that make a participant eligible to receive a specific intervention type at a specific time (decision points).

At each decision point (early morning, morning, midday, and evening), the system evaluates which intervention options a participant is eligible to receive, and randomly chooses one intervention option from that list. Then the participant is randomly assigned to either receive or not receive that intervention message (with a 50-50 probability).
Behavioral: Nudge
Nudge is a smartphone-app-based micro-randomized trial that tests the effect of 7 intervention message types based on behavior change techniques on daily goal attainment. Participants have three daily goals: weigh daily, red foods goal, and active minutes goal.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percent of person-days with same-day weighing
Time Frame: from Baseline to Week 12
Percent who weighed after the message randomization time until the end of the day (at the participant-day level) across the 12-week study
from Baseline to Week 12
Percent of person-days with next-day weighing
Time Frame: from Baseline to Week 12
Percent who weighed the day after the message randomization (at the participant-day level) across the 12-week study
from Baseline to Week 12
Percent of person-days met active minutes goal on same day
Time Frame: from Baseline to Week 12
Percent who met active minutes goal after the message randomization time until the end of the day (at the participant-day level) across the 12-week study
from Baseline to Week 12
Percent of person-days met active minutes goal on next day
Time Frame: from Baseline to Week 12
Percent who met active minutes goal the day after the message randomization (at the participant-day level) across the 12-week study
from Baseline to Week 12
Percent of person-days met red foods goal on same day
Time Frame: from Baseline to Week 12
Percent who met red foods goal after the message randomization time until the end of the day (at the participant-day level) across the 12-week study
from Baseline to Week 12
Percent of person-days met red foods goal on next day
Time Frame: from Baseline to Week 12
Percent who met red foods goal the day after the message randomization (at the participant-day level) across the 12-week study
from Baseline to Week 12

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of active minutes
Time Frame: from Baseline to Week 12
Total number of active minutes on the day of message randomization (at the participant-day level) across the 12-week study
from Baseline to Week 12
Proximal effect of message on total red foods today
Time Frame: from Baseline to Week 12
Total number of red foods on the day of message randomization (at the participant-day level) across the 12-week study
from Baseline to Week 12
Mean weight change
Time Frame: from Baseline to Week 12
Mean weight change across participants
from Baseline to Week 12

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of North Carolina, Chapel Hill

Investigators

  • Principal Investigator: Carmina G Valle, PhD, University of North Carolina, Chapel Hill

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 12, 2019

Primary Completion (Actual)

September 16, 2019

Study Completion (Actual)

September 16, 2019

Study Registration Dates

First Submitted

February 7, 2019

First Submitted That Met QC Criteria

February 7, 2019

First Posted (Actual)

February 11, 2019

Study Record Updates

Last Update Posted (Actual)

November 13, 2019

Last Update Submitted That Met QC Criteria

November 11, 2019

Last Verified

November 1, 2019

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 16-0775

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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