On the classification of ballistocardiograms.

An improvement of Brown's classification is described... The new classification reflects the amplitude and time-relation changes of the Bcg. A method for estimating the mean values of Bcg elements, based on the principle of calculation of all corresponding values during the complete 2-3 respiratory cycles is described

An improved classification of ballistocardiographic changes.

On the basis of a critical analysis of the most frequently used classifications of ballistocardiographic changes, an improved classification is proposed, which simultaneously respects the degree of pathological changes appraised according to Brown; the configurations and amplitudes of waves and segments, as well as their dependences on time. The proposed classification essentially accepts the symbols used in the classifications used up to the present, thus obviating errors and mistakes which the new classification might involve. The improved classification facilitates a better differentiation of first-degree pathological changes into those caused by disturbances of cardiovascular dynamics and those due to extracardial factors.