Participant Recruitment: Mobile Sensing Study of Postpartum Mood and Daily Behavior

Understanding the relationship between everyday behaviors and postpartum well-being (For U.S. residents)

Overview

After childbirth, many aspects of daily life change — including sleep, physical activity, routines, and smartphone use. This study aims to understand how these everyday behaviors relate to the mental and physical well-being of postpartum women. Using your own smartphone and wearable device, we will collect activity data in the background alongside brief daily questionnaires. This study is conducted by the Center for Spatial Information Science (CSIS), The University of Tokyo, in collaboration with Information School at the University of Washington.

Eligibility Requirements

You may be eligible if you meet all of the following criteria:

Woman currently residing in the United States (Washington State)
Age 20 or older
Own a smartphone (iOS or Android)
Currently raising a young child (preferably under 12 months old)
First-time mothers are prioritized

You may not be eligible if you are raising two or more children, or if your smartphone does not have enough storage space to install the data collection app.

Study Procedure

Data collection will last 3 months (12 weeks). The initial setup takes approximately 15–30 minutes.

1 Review the study information and provide informed consent via an online form
2 Install the data collection app on your smartphone and complete initial setup
3 The app automatically collects sensor data in the background
4 Complete brief daily questionnaires (morning and evening, approx. 3–5 minutes each)
5 After the data collection period ends, receive compensation based on the amount of data submitted

Data Collected

Motion sensors (accelerometer, gyroscope, etc.)
Location-related data (GPS, Wi-Fi, barometer, etc.)
Physical activity indicators (step counts, mobility types, etc.)
Sleep duration and quality
Smartphone usage (calls, screen status, used apps, etc.)
Weather information
Physiological data (heart rate, skin temperature, etc.)
Audio events: ambient noise level and infant crying time (raw audio is NOT stored)
Past physical activity data (step counts, etc., up to 2 years, via Apple Health / Google Fit)

Compensation

Compensation will be provided as an Amazon Gift Card, up to a maximum total of $300. You will receive $20 for each week in which you provide sufficient valid data (12 weeks × $20 = $240). For every 4 consecutive weeks of complete data, you will receive an additional $20 bonus (up to 3 bonuses = $60).

Privacy

Personal information and study data will be pseudonymized with a code, and the correspondence table linking them will be stored separately under lock and key. When publishing research findings, no information that could directly identify individuals will be used. This research has undergone ethics review at the University of Tokyo and the University of Washington.

Participation is entirely voluntary. You may withdraw at any time without any negative consequences.

Ready to Participate?

Contact

For inquiries about this study, please contact the research team. If you have been injured or otherwise harmed by participating, please also reach out.

postpartum-study@csis.u-tokyo.ac.jp