Reliability of electrogustometry for the estimation of taste thresholds

Electrogustometry has been used as a clinical tool for diagnosis and assessment of a variety of conditions. Several studies which have estimated electrogustometric taste threshold have reported good test-retest reliability but there is some evidence that thresholds measured this way may decrease with practice. In this study, repeated testing of the right and left sides of the tongue of two subjects over 80 sessions resulted in considerable session-to-session variability for both subjects, and three of the four sets of threshold estimates decreased systematically with continued testing. Two of the four data sets continued to show systematic decreases when the first 10 sessions were omitted from analysis to allow for any initial unfamiliarity with the testing procedure. This suggests that estimates based on few tests should be interpreted with caution, particularly when used for evaluation or monitoring of interventions.