FAQ

About the Study

Approvals

  • Was this study approved by MIT?

    This study has been approved by MIT's COUHES (#1511302833) and MGH IRB (#2015P001913/MGH). Our protocol is reviewed annually by MIT COUHES and MGH IRB.

Data

  • Can I download this data?

    Unfortunately not – we have yet to release de-identified data.

  • How much data have you collected?

    We have collected data from 39 depressed individuals and 4 healthy controls over the course of 2 years.

Sensors and Sensor Data

  • Which data is recorded with the Empatica E4 sensor?

    The E4 sensor from Empatica measures (1) skin conductance, (2) skin temperature, (3) heart rate, and (4) 3-axis acceleration data. More information can be found here.

  • How is the E4 sensor data collected?

    The E4 sensors were worn continuously by the participants for 8 weeks on both wrists. The measurements were uploaded regularly (~every 24 hours) to the Empatica server.

Mobile Phone Data

  • Which information was collected from phones?

    The app collected:
    1. Timing and sender or recipient phone numbers of calls and text messages
    2. Timing of screen on/off
    3. Location
    4. Timing of application use and the name of application process
    5. Device information (e.g. phone type, WiFi/Bluetooth mac address, etc.)
    We did not record SMS messages, phone conversations, internet browsing history, or which keys were pressed on the phone.

  • How is the mobile phone data collected?

    All the collected data is encrypted on the phone and then sent to the server using the movisensXS app. More information can be found here.

  • How confidential is the mobile phone data?

    Software on the mobile phones would automatically de-identify the collected data by encrypting all the to/from phone numbers and sender/recipient names.

Recruitment

  • How were subjects recruited for the study?

    Subjects were enrolled from primary care and psychiatry clinics at Massachusetts General Hospital (MGH) by physician referral, fliers, internet, radio, call lists of individuals willing to be contacted for research, and general advertisements.

  • What was the inclusion criteria for the subjects?

    The inclusion criteria for the study were as follows:
    1. Adults (age 18-75)
    2. Able to read, understand, and provide written informed consent in English
    3. Meet criteria for a primary psychiatric diagnosis of major depressive disorder for at least 4 weeks, according to the M.I.N.I. (Mini International Neuropsychiatric Interview)
    4. Hamilton Depression Rating Scale (HDRS) total score of at least 18
    5. Engaged in or willing to be referred for clinical care for depression treatment as usual (antidepressants and/or psychotherapy)
    6. Must have measurable skin conductance/electrodermal activity (as assessed at the screening visit), and healthy-looking skin at the wrist location
    7. Must own a working Android smartphone (Android 2.3+) and use it regularly
    8. Must be willing to wear E4 sensors on both wrists
    9. Must be willing to answer study surveys and record weekly audio-diary on their smartphone
    10. Must own a Windows PC (or tablet) or a Mac computer (or laptop)
    11. Must have access to Internet service every day