Metrics and Measures

• There are numerous types of data that you can collect from consumer wearables.
•  For example, wearable devices can track anything from accelerometer to sleep staging, to heart rate and even blood oxygenation! 
• Here’s a  list of some of the most common types of data collected by researchers in academia. 
• As you can see, the data types are split into two categories: metrics and measures.
• While often used interchangeably, the main- and very important distinction between the two- is the level of post-processing from the wearable company. A measure, for example, is the data collected without further calculations applied to it. It’s therefore considered more ‘raw.’ A metric, however, is when the wearable company derives a value from algorithms they’ve internally applied based on measures that’ve been collected. 

• While measures should be consistent across devices and brands, one of the challenges for health researchers in the consumer wearable market is the lack of standardization of metrics. A stress score on a Garmin, for example, is calculated differently than a stress score on an Oura ring. But not to worry- metrics are still great and extremely valuable to your research.

• The main takeaway here is to remember not to compare metric scores across devices, and to ensure that you ask the device companies to share how these metrics are calculated, to help with transparency in your research.

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