Figure 1 A: The BigThumb system. With two thumbs of users on the device, a bECG will be collected. B: Software interface of the BigThumb. Users are asked if there is a symptom when bECG is collected. C: A bECG collected by a patient with atrial fibrillation. D: Summary of bECG in one-month duration. The red points show the bECG with atrial fibrillation and the green points show the sinus rhythm.

Table 1. Characteristics Between Patients in BT and TF Groups