Fig. 2.

Surgical interventions for essential tremor. The four options are shown with the grading of usefulness of the Movement Disorder Society [29]. The bars show the mean improvement in percent for the different interventions reported in the studies mentioned in the text. The lateralized TRS is summarizing tremor severity items only on the side contralateral to the intervention. The total TRS covers tremor severity, performance tests, and activities of daily living. The dotted line is the average improvement of the lateralized score exerted by medications (see Fig. 2). The grading of clinical usefulness does not reflect the strength of the effect size of the intervention but the strength of published evidence.