Indexes for identification of abnormal tremor using computer tremor evaluation systems

The authors consider methods of formulating indexes to identify abnormalities in tremor appropriate for computerized tremor analysis systems. Characterization of amplitude, frequency, and "harmonicity" are considered as well as how to combine several such characteristics into a single index to discriminate normal from abnormal tremor effectively. The methodological issues discussed here should be of interest to researchers and clinicians working with tremor in general and to both users and developers of computer tremor analysis systems.