A device that may include, or communicate with, sensors such as an electrocardiogram (ECG) sensor, an accelerometer, and/or a photoplethysmograph (PPG) detects sleep-disordered breathing (SDB) events of a patient based on signals from the sensors. The device may have a processor configured to make the detection(s). In an example, the processor may access a memory with processor control instructions. The instructions may be adapted to configure the processor to carry out the detection methodology. The method may include analysing an ECG data of the patient from a signal generated by the ECG sensor, pulse oximetry data of the patient from a signal generated by the PPG, and a three-dimensional (3D) accelerometry data of the patient from a signal generated by the accelerometer to detect the SDB events. The device and methods may be used for screening, diagnosis and monitoring of respiratory disorders.