Long-term tremor recordings in parkinsonian and essential tremor.

We have recently developed a method of long-term EMG recording (Bacher et al., 1989), which has proven suitable for the quantification of pathological tremor. In the present paper we show that (1) the principal parameters of the method (tremor occurrence, tremor intensity, tremor frequency) are highly reproducible with intraclass correlation coefficients in the order of 0.9, (2) that the method has both a high specificity (87.5%) and sensitivity (96%) for detection of pathological tremor, and (3) that it can be useful for examining agonist-antagonist muscle activation under everyday conditions.