Diagnostic test performance of screening questions for neurosensory hand-arm vibration injury.

Background: There is a need for efficient screening for hand-arm vibration injury.

Aims: To evaluate the diagnostic test performance of screening questions for neurosensory injury in relation to clinical testing among hand-arm vibration (HAV)-exposed workers.

Methods: HAV-exposed subjects responded to a screening survey on subjective perception of touch, warmth, cold, and vibration, as well as grip strength and manual dexterity. Perception of monofilament, two-point discrimination, temperature rollers, and tuning fork was tested on the index and little fingers of both hands, while grip strength was tested using a hydraulic dynamometer. Diagnostic test performance characteristics were calculated based on crosstabulation of survey responses and outcomes of clinical testing.

Results: Our study recruited 225 subjects with exposure durations between one and 43 years. The sensitivity and specificity for the question about impaired ability to feel touch compared with monofilament was 65% and 71%; impaired ability to feel heat compared with temperature rollers 50% and 75%; impaired ability to feel cold compared with temperature rollers 39% and 77%; impaired ability to feel vibration compared with tuning fork 49% and 84%; reduced grip strength compared with hydraulic dynamometer 83% and 58%; and difficulty fastening buttons compared with two-point discrimination 40% and 76%, respectively.

Conclusions: The diagnostic test performance of the currently used screening survey for neurosensory injury among HAV-exposed workers needs to be improved. Future development should focus on establishing more specific questions, balanced response alternatives, and a more sophisticated interpretation of the responses, possibly using an index made up of several screening questions.