All tremor research and treatment would be improved if there was an easy way to quantify and rate tremor severity. It is difficult to quantify tremor since it takes so many descriptive statistics to capture tremor activity. Many different values are reported in published research and even the TremorLab® generates many values with the frequency mean, frequency spread, amplitude and percent time - plus multiple advanced FFT-based values. This makes it difficult to simply quantify tremor. The UPDRS, as a rating scale for one type of tremor, is subjective and only has four levels. There is a better way to generate a more quantitative and objective measure.

The TremScore™ has been developed as one possible way to capture the most important aspects of the tremor statistics in a single number. The formula currently employed in TremorLab multiplies together four separate statistics to come up with a single number. It is assumed that a tremor is “worse” and should have a higher score if:

1. The frequency is greater [Frequency Weighted Mean or FWM]
2. The distribution of the frequency is narrower [1/Frequency Spread or 1/FS]
3. The amplitude is greater [Tremor Amplitude of TA]
4. The time that tremor is present is greater [Percent Tremor Time or PTT]

The formula for TremScore is currently: FWM * 1/FS * TA * PTT

The reciprocal of the Frequency Spread is used to convert this value which is greater for more diffuse tremors into a measure in which the value is greater for tighter tremor distributions.

The TremScore has not been clinically tested and clinical testing may indicate that some of the factors should be weighted to produce a more useful score. All researchers are encourage to see how the TremScore works for quantifying their patients and subjects against other measures of tremor severity.

If a valid method for generating a TremScore can be developed, it will make it much easier for researchers to share and compare data, for neurologists and physicians to track changes in their patients over time and medication regimens, for patients to track their own tremor over time, and for drug trials to measure possible drug tremor side effects. Having such a simple score might encourage the measurement of tremor as a standard part of a physical exam to detect tremor that might be an early indicator of Alzheimer’s or other ailments. In industries such as welding in which tremors sometimes develop, it could be useful both as an initial physical test to screen and document any problems that may exist when a worker is hired and as a routine test to detect the onset of tremor.

The Tremorometer® already makes tremor measurement affordable, easy and standard - a good TremScore would make it more useful.