Pitfalls of Medically Accurate Measurements
In this webinar, Walt Maclay covers common bio-sensors used in wearables for remote patient monitoring and how to get medically accurate measurements.
- Heart rate. Heart rate is simple to implement in theory, but difficult to measure on the wrist. Measuring the electrical EKG signal requires good contact with the skin, which can be difficult. A more reliable technique is pulse plethysmography or PPG, but there are two types, and the one that is most reliable only works on the fingers or the ears.
- Skin temperature. Skin temperature varies greatly, so it’s not a good indicator of core temperature (to detect fever, for example) except at a few locations.
- Measuring EKG. Measurement points have to be rather far apart (at least 1½ inches on the chest). That’s a significant issue if the device is too small. It’s particularly difficult to measure EKG on the wrist.