Vibrotactile threshold testing in occupational health: a review of current issues and limitations

Quantitative cutaneous vibrotactile threshold measurement has been proposed as a useful method for assessing peripheral nervous system function in occupational and environmental neuroepidemiology. It allows rapid, quantitative, and nonaversive assessment of peripheral nervous system function. Acceptance of this method is currently limited, however, because of poor standardization of methods, the lack of data regarding the effects of age, gender, and other covariates, and minimal demonstration of association between vibrotactile threshold and conventional measures of peripheral nerve function. Data from a series of validation studies intended to address some of these problems are presented and relevant literature is discussed. Specifically, results of studies in which reliability and time efficiency of testing protocols were measured, the effects of covariates on measurement of vibrotactile threshold were estimated, and vibrotactile thresholds were compared to physical examination and electrophysiologic evaluation are discussed. Recommendations are made regarding choice and standardization of testing protocol, covariates, and issues for future research.