Investigation of a portable performance measurement system for neurologic screening in clinics.

Motivated by the need for clinical screening for early detection of neurologic disease, a prototype portable instrument dubbed the human performance multimeter (HPMM) was developed. The HPMM is based on a set of lab-based performance capacity tests developed and evaluated over the last two decades. We attempted to integrate selected functionality of a set of modular lab-based instruments into a single, small package. In the present study, a 4th generation prototype was developed and evaluated for usability, measurement repeatability, and preliminary measurement validity. Five performance capacity tests (upper extremity coordination, isometric grip strength, simple response speed, rapid alternating movement, and steadiness/tremor) were administered to twenty healthy adult volunteers. Short-term reliability was investigated using a test-retest protocol. Most measures were found to possess good test-retest reliability (r>0.75). Preliminary validity was investigated by comparing results to those obtained with non-portable devices that served as models for the HPMM. Results were in good agreement with those instruments. It is concluded that measures of good fidelity can be obtained with this type of instrument.