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Determining Sample Size and Length of Follow-up for Smartphone-based Digital Phenotyping Studies

This on-demand webinar does not offer CE credit.

Barnett I, Torous J, Reeder HT, Baker J, Onnela JP. Determining sample size and length of follow-up for smartphone-based digital phenotyping studies [published online ahead of print, 2020 Oct 12]. J Am Med Inform Assoc. 2020;ocaa201. doi:10.1093/jamia/ocaa201

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Ian J. Barnett, PhD
Assistant Professor of Biostatistics
Department of Biostatistics, Epidemiology, and Informatics
University of Pennsylvania


Hannah Burkhardt
PhD candidate
University of Washington School of Medicine
Biomedical Informatics and Medical Education

Statement of Purpose

Smartphone-based digital phenotyping studies use patient smartphones to collect ecological momentary assessment and sensor data. There is a lack of formal guidelines for the design of new digital phenotyping studies so that they are powered to detect both population-level longitudinal associations as well as individual-level change points in multivariate time series. In particular, determining the appropriate balance of sample size relative to the targeted duration of follow-up is a challenge. We present sample size and power calculations to guide the design of digital phenotyping studies.

Target Audience

The target audience for this activity is professionals and students interested in biomedical and health informatics.

Learning Objectives

The general learning objective for all of the JAMIA Journal Club webinars is that participants will

  • Use a critical appraisal process to assess article validity and to gauge article findings' relevance to practice

After this live activity, the participant should be better able to:

  • Use the study‚Äôs sample size calculator to determine an appropriate sample size and length of follow-up duration for digital phenotyping studies.
  • Identify the types of appropriate data analyses that can be performed with the intensive longitudinal data collected through digital phenotyping studies.

Commercial Support

No commercial support was received for this activity.

Disclosures for this Activity

The following presenters, planners, and staff who are in a position to control the content of this activity disclose that they and their life partners have no relevant financial relationships with commercial interests:

JAMIA Journal Club planners: Hannah Burkhardt, Kirk E. Roberts
JAMIA Journal Club presenter: Ian J. Barnett
AMIA Staff: Susanne Arnold, Pesha Rubinstein


Dates and Times: -
Type: Webinar
Course Format(s): On Demand