A processing device including an interface unit, a first slot, and a transmission unit is provided. The interface unit is configured to receive a plurality of physiological monitoring signals. The first slot is configured to hold a first analysis module. When the first analysis module is inserted into the first slot, the first analysis module analyzes a first signal group to generate a first analysis result. The first signal group includes at least two of the physiological monitoring signals. The transmission unit outputs the first analysis result to at least one external device.
