Before doing an expensive and inaccurate field experiment, we can calculate the expected cost per QALJ [1] by taking the following variables: - Estimated accur

Before doing an expensive and inaccurate field experiment, we can calculate the expected cost per QALJ [1] by taking the following variables: - Estimated accuracy and recall of the test - Estimated probability of user doing a follow-up based on feedback from watch - Estimated price of a doctors visit - Estimated probability of a follow-up test using medical grade equipment (based on additional data) - Estimated cost per QALJ of the extra test and follow-ups - Estimated prevalence of arrhythmia among Apple Watch users based on age-group I expect, but do not know, the Apple Watch tests to prove to be a net-negative compared to doing nothing. [1] Quality Adjusted Life Year