Characterisation of the Clothespin relocation task as a functional assessment tool

The Clothespin Relocation Task has been adapted from an arm training tool into a measurement instrument. By timing the movement of three clothespins from a horizontal bar to a vertical bar and back, the coordination of arm and hand can be
explored. It can be used to measure the performance of a prosthesis system, controller, or user compensations. It is particularly sensitive to revealing the compensations made by the user.

To be fully useful the measures need to have the psychometric properties investigated. This test is part of that process. The characteristics of an able bodied population have been measured to gain an understanding of the statistical properties of the test. Fifty adults (29 males, 21 females, mean age 31) were tested with five runs of three clothespins being moved up and down. Ten subjects returned twice to
observe repeatability.

There was a non Gaussian range of times, from 2.5s to 7.37s. Mean time for Up was 4.1s and 4.0s for Down with a skew towards the faster times of 0.57 for Up and 0.97 for Down. Over the three sessions there was a small increase in speed 4.1+/- 0.5s first run Down to 3.5 +/-0.4s for third.