The Dutch EQUAL study demonstrated that the Apple Watch is more effective in detecting atrial fibrillation (Afib) in high-risk patients than standard cardiology care.[1][2] An extensive clinical study with more than 400,000 participants lasting eight months confirmed the high accuracy of the ECG function built into the Apple Watch.[1] Of the 2,161 patients whose watch alerted them to atrial fibrillation, the symptoms were confirmed in 84% of them on further EKG examination.[1][2] 34% of the total number of alert patients were actually diagnosed with atrial fibrillation.[1][2] The ECG app in the Apple Watch achieves 99.6% accuracy in classifying a normal heart rhythm and 98.3% in detecting atrial fibrillation.[5] The probability of a false alarm is low - only 0.5% of study participants received an afibrillation warning, meaning that healthy users will not be unduly alarmed.[3] The results of the study confirm that the Apple Watch can reliably warn of a health problem and has the potential to save lives by early diagnosis of atrial fibrillation.