Validity and reliability of rapidly alternating movement tests

Two studies investigated the interrater reliability and concurrent validity of tests of rapidly alternating movement, Study 1 examined the interrater reliability of three different tests, ''finger tapping'' to the adjacent thumb, ''table tapping,'' and ''hand to thigh'' alternating movements. Using normal participants the results indicated poor interrater agreement for the ''hand to thigh'' test and modest relationships for both types of finger tapping. However, for each test the number of recorded repetitions differed significantly between raters, Study 2 examined the concurrent validity of two mechanical measures of finger tapping. The scores of 36 normal participants was compared using a mechanical digital counter and a calculator. Results indicated that the use of the calculator as a counter was highly related to the results with a mechanical digital counter. Conclusions suggested the use of a mechanical apparatus is more reliable than human observations, In addition, the use of an inexpensive apparatus will produce results similar to the manual finger tapping apparatus commonly used in neuropsychological batteries.