<P>PROBLEM TO BE SOLVED: To provide a method and system for detecting atrial fibrillation in a patient. <P>SOLUTION: This method 100 and system 500 monitors the blood oxygen saturation level over a period of time. The method and system produces a plethysmographic waveform 300 (120) from the monitored blood oxygen saturation level, and analyzes the plethysmographic waveform and detected intervals (140, 145) and determines whether the patient is in atrial fibrillation. The method 100 and system 500 is preferably implemented in a software application and may be configured to report to the user on the current state (370) of atrial fibrillation (AFIB) and a current trend (390). <P>COPYRIGHT: (C)2009,JPO&INPIT 
FALSE POSITIVE ALARM REDUCTION IN SPO2 ATRIAL FIBRILLATION DETECTION USING AVERAGE HEART RATE AND NIBP