1. An evaluation method, in particular to be implemented on implantable cardiologic devices, such as defibrillators or cardiac pacemakers, for determination of time stationarity of measured physiological, 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, in particular of correlated symbol series to anticorrelated symbol series; 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.