Tremor assessment and quality of life measurements.

Essential tremor (ET) can be measured objectively by physiological techniques, simple tests of the tremor's impact on function, or subjective use of clinical rating scales. The methods of measuring ET and its influence on patients are reviewed. Multidimensional evaluations are recommended for the assessment of the severity of ET in clinical trials. The term "detractor" describes the relationships between ET and the disability and handicap that it produces.