For a general overview of SensorKit, refer to the first post in this series—Answering novel questions.
How do I get approval to use SensorKit?
Prior to implementing SensorKit for a research project, the study team will need to receive approval from Apple. A SensorKit Research Proposal must be filled out and submitted to Apple for review. If using MyDataHelps as your platform for collecting SensorKit, please contact us to complete your proposal. The research proposal will contain:
Investigators and institution overview
Requested sensors as well as research justification
Method by which you will collect the data
Standards by which you will secure and retain the data
It is best to start the submission process immediately so that you may finalize your protocol document after approval. As necessary, consider including appendices with your research proposal when you require additional space in your submission. If you plan to use MyDataHelps and are approved, you may be required to complete an agreement that allows CareEvolution to share data with your team.
How do I enable SensorKit?
If you receive Apple approval to implement SensorKit, you’ll be granted development entitlements to permit the collection of SensorKit data from your project’s participants. In addition to prompting participants for SensorKit permissions, you’ll also want to obtain eConsent. Participant privacy is paramount; if you collect SensorKit data, make sure participants are also aware of how you plan to keep it secure by including this information in your consent.
Once a participant has agreed to the SensorKit permissions, you’ll receive the data after a 24-hour embargo. Even then, some SensorKit data is batched daily, so if you miss that day’s upload, it could be an additional day before data is received.
What SensorKit data will I receive?
Be prepared for a large volume of SensorKit data. For example, accelerometer data alone for a single participant can be > 3 GB of uncompressed data per day. Other sensor types tend to be closer to 3.5 MB of uncompressed data per participant per day, which can still add up with high enrollment over a study’s duration—100 participants over a 60-day study duration would be 21 GB for that sensor alone.
SensorKit data has a hierarchical data structure in a JSON format. Note that some data is provided in a privacy-focused fashion. For example, Visits data does not contain precise GPS coordinates for locations, but rather each location is given a random identifier and a distance from home. Please refer to our SensorKit Export Overview user guide article for additional information.