A quantifying of the function of a beating heart is disclosed, in which a signal is recorded with an accelerometer placed on the chest of a person. A plurality of segments of the signal are formed, which are aligned and filtered with a band-pass filter having a lower cutoff frequency below 1 Hz and an upper cut-off frequency in the range 100-500 Hz. A mean segment is then determined, in which a first temporal feature is determined. A measure is then determined based on at least one of the signal strength of the first temporal feature and the location in time of the first temporal feature. The determined measure is then provided as output information.
