The invention provides a monitoring device (1) for attachment to a stance of a subject. The device comprises a data collector (2) and a processor (3) as two separate parts which can be detachably joined such that physiological signals which are detected by the data collector can be transferred to the processor for signal processing and provision of monitoring data. At least one of the data collector and the processor comprises a transducer which can convert the physiological signal to a data signal which can be processed electronically. The data collector is adapted for adhesive contact with a skin surface, and may comprise an adapter (6) for the detachable attachment of the processor.