The present invention relates to a method of analysing cardiac data relating to a patient, comprising: providing cardiac data relating to the patient—；optionally by using a means for providing physiological data (20)； determining one or more properties of the data, wherein the or each property is determined over a particular context length, the context length being selected based on the or each property—；optionally using an analysis module (24)； comparing the or each property against a respective predetermined threshold value, thereby to indicate a probability of the patient experiencing a cardiac event—；optionally using a means for providing an output (26)； and providing an output based on the comparison. A system and apparatus corresponding to this method is also disclosed.
