Quantitative instrumental measurement of tardive dyskinesia: a review

In this paper we review currently available quantitative instrumental techniques for the assessment of tardive dyskinesia (TD). We discuss the advantages and disadvantages of the use of accelerometers, electromyography, force gauges, position transducers, and Doppler ultrasound from both a diagnostic and a utilitarian perspective. Data obtained using these techniques appear to correlate significantly with patient scores on clinical rating scales. In some cases, the use of these techniques has facilitated the detection of subclinical dyskinesia and helped to differentiate TD from other movement disorders. We believe that a review of these qualitative techniques will be of interest to the clinician, as well as to investigators involved in studying TD.