To determine HRV, Apple Watch captures a tachogram—a plot of the time between heartbeats—every two to four hours. Beginning with watchOS 5.1.2, users may al...

https://www.apple.com/jp/healthcare/docs/site/Apple_Watch_Arrhythmia_Detection.pdf

the distribution of sensitivity and specificity values in the validation group. Each point in the distribution is a sensitivity or specificity value calcula...

https://www.apple.com/jp/healthcare/docs/site/Estimating_Sleep_Stages_from_Apple_Watch_Sept_2023.pdf

learning algorithm and therefore doesn’t rely on training data at any point. Audiograms from the National Health and Nutrition Examination Survey (NHANES) a...

https://www.apple.com/jp/health/pdf/Hearing_Health_Features_on_AirPods_Pro_2_October_2024.pdf