Table 1.

Tremor types in Parkinson disease.

Type I. Pure resting tremor

Type II. Mixed resting and action tremor with similar frequencies∗

II-R. Action tremor with a time lag

II-C. Action tremor without a time lag

Type III. Pure action tremor

Type IV. Mixed resting and action tremor with different frequencies∗∗

^∗Difference <1.5 Hz; ^∗∗difference >1.5 Hz.