NCT07783724

Brief Summary

To evaluate the impact of two personalized nudging strategies delivered as pop-up notifications via the Fitbit app on user step count. Specifically, to personalize the following parameters of the pop-up notification system: message content, and timing (hr of the day).

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
13,463

participants targeted

Target at P75+ for not_applicable

Timeline
Completed

Started Feb 2024

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

February 26, 2024

Completed
6 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 26, 2024

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

August 26, 2024

Completed
2 years until next milestone

First Submitted

Initial submission to the registry

August 21, 2026

Completed
4 days until next milestone

First Posted

Study publicly available on registry

August 25, 2026

Completed
Last Updated

August 25, 2026

Status Verified

August 1, 2026

Enrollment Period

6 months

First QC Date

August 21, 2026

Last Update Submit

August 21, 2026

Conditions

Keywords

activityexercisesedentaryartificial intelligence

Outcome Measures

Primary Outcomes (1)

  • Change in step count from baseline.

    The average daily step count during the final month minus baseline daily step count during one month before enrollment.

    One month prior to enrollment (Baseline) to the second month post-enrollment (60 days total enrollment).

Study Arms (4)

Control

NO INTERVENTION

Participants use Fitbit devices, without the addition of the nudge intervention.

Random

ACTIVE COMPARATOR

Participants use Fitbit devices, with the addition of randomly deployed nudge interventions (random timing and theme).

Behavioral: Mobile App Push Notification (Random Selection)

Behavior Science

ACTIVE COMPARATOR

Participants use Fitbit devices, with the addition of nudges deployed based on behavior science heuristics.

Behavioral: Mobile App Push Notification (Behavior Science Heuristics)

Reinforcement Learning

EXPERIMENTAL

Participants use Fitbit devices, with the addition of nudges deployed based on a reinforcement learning algorithm.

Behavioral: Mobile App Push Notification (RL)

Interventions

Participants use Fitbit devices, with the addition of nudges deployed based on behavior science heuristics.

Also known as: Nudges
Behavior Science

Participants use Fitbit devices, with the addition of nudges deployed based on a reinforcement learning algorithm.

Also known as: Nudges
Reinforcement Learning

Participants use Fitbit devices, with the addition of randomly deployed nudge interventions (random timing and theme).

Also known as: Nudges
Random

Eligibility Criteria

Age22 Years - 60 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Age 22-60 years
  • \[For Phase 2 \& 3\] Daily average steps 1 month prior to recruitment is less than 8000
  • Owns a Fitbit device \& smartphone with Fitbit app
  • Willing to share a month of step count data prior to enrollment data
  • Wear a Fitbit device regularly (user-reported)

You may not qualify if:

  • Advised by a doctor to avoid exercising or limit physical activity
  • Current employees of Alphabet
  • \[For phase 2\] Have participated in Phase 1 of the study
  • \[For phase 3\] Have participated in Phase 1 or 2 of the study

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Google Office (Digital Study)

Mountain View, California, 94043, United States

Location

Related Links

MeSH Terms

Conditions

Sedentary BehaviorMotor Activity

Condition Hierarchy (Ancestors)

Behavior

Study Officials

  • James A Taylor, MD

    Google LLC.

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
PARTICIPANT
Purpose
OTHER
Intervention Model
PARALLEL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 21, 2026

First Posted

August 25, 2026

Study Start

February 26, 2024

Primary Completion

August 26, 2024

Study Completion

August 26, 2024

Last Updated

August 25, 2026

Record last verified: 2026-08

Data Sharing

IPD Sharing
Will not share

Locations