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That's surprising, since the heart rate monitors on many phones are quite accurate. Many will actually give an ECG-like trace indicating brief changes in blood
by falcrist 8y ago
That's surprising, since the heart rate monitors on many phones are quite accurate. Many will actually give an ECG-like trace indicating brief changes in blood pressure. I don't see any good reason they shouldn't be extremely accurate.
- pc86 8y agoWell unless you're wearing a cuff you're not getting any blood pressure readings on your phone, and any "ECG-like trace" is a doodle at best as there's no electrical monitoring. Even chest straps that measure electrical output don't give you an ECG display.
- falcrist 8y agoI'm not suggesting that absolute blood pressure is being measured by a phone PPG, only relative changes. Far from being just a doodle, the PPG readout ("ECG-like trace") comes from changes in skin reflectivity that indicate relative changes in blood pressure. [1] Obviously this isn't as good as an actual ECG (and can be disrupted by movement), but it's far more information than is needed to accurately track heart rate. These devices can be as accurate as a pulse oximeter [2], though they don't account for the movement of the user. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4822420/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4822420/ [2] https://www.ncbi.nlm.nih.gov/pubmed/28464700 https://www.ncbi.nlm.nih.gov/pubmed/28464700
- deleted 8y ago[deleted]