I can only imagine the study that would need to be done to confirm this "90% accuracy" claim. In fact, I have to imagine it because I can pretty much guarantee that it hasn’t been done. https://twitter.com/TheNBACentral/status/1273667511788109829">https://twitter.com/TheNBACen...
Briefly, you’d have to track thousands of people’s metrics, using the data to make a prediction - “yes, covid-19”, or “no, healthy”, and then assess if you’re right over time. Then you’d assign them to batches of false negatives, false positives, true negatives, true positives,
True positive - Oura ring correctly predicts C-19.
True negative - Oura correctly predicts healthy
False negative - Oura says healthy, you get C-19
False positive - Oura says C-19, you stay healthy
Then calculate accuracy as (TP + TN)/(TP + FP + TN + FN).
Was this done? No chance
True negative - Oura correctly predicts healthy
False negative - Oura says healthy, you get C-19
False positive - Oura says C-19, you stay healthy
Then calculate accuracy as (TP + TN)/(TP + FP + TN + FN).
Was this done? No chance