“…14,26,28,36,37,[42][43][44] At the same time, the advantage of shortterm indices lies in their good reproducibility. 38 The analysis of recent studies showed that among conventional methods of heart rate variability analysis, 3,9 time domain methods 16,23 are preferred less, while frequency domain methods 2,13,15,25,33,34,41,[44][45][46] are preferred more, as is their use in combination, 47,48 which is caused by the rapid development of computer technologies that deal with digital processing of signals, including spectral analysis methods, such as multifractal and wavelet transform analysis. 2,37,38,41,47,49 One could note the diversity of methods that researchers use to mathematically process and analyze experimental data on heart rate variability indices.…”