Patent ID: 6731972
Filing Date: 2004-05-04
Classification: A61B,A61N,Y10S

Abstract:
An evaluation method, for determination of time stationarity of measured physiological signals, in particular cardiologic signals, comprising the following steps:recording values of a physiological signal during a certain measuring period for obtaining a time series of signal values; dividing the obtained time series of signal values into individual segments; mapping successive subsets of the individual signal values in a segment on associated symbol series according to a criterion of whether a respective signal value increases or decreases as compared to a preceding signal value; determining frequencies of the varying symbol series; determining a testing parameter which reflects a frequency ratio, within a segment, of symbol series of varying correlation stages; determining a relative difference of the testing parameters of two adjacent segments; and comparing the relative difference of two testing parameters with a given threshold as a criterion for the stationarity of the time series of the recorded physiological signal.