The performance of scorers using the University of Utah and Department of Defense Polygraph Institute (DoD PI) physiological detection of deception chart evaluation rules were compared to discover if differences in laboratory-based decision accuracy rates are due to chart evaluation rules. Four scorers (two based at the DoD PI , two based at the University of Utah) evaluated the charts from 100 polygraph examinations (50 deceptive, 50 nondeceptive). We attempted to isolate scorer ability by equating the rules for making veracity decisions, number of charts used, and number of data channels considered. There was no evidence, when these variables were held constant, that scorers differed on the proportion of correct, incorrect, or no opinion decisions rendered. Results suggest no differences in chart scoring ability among scorers based at the two institutions. Observed differences in accuracies for Utah and DoDPI scoring systems may be due to differences in veracity decision rules, the number of charts evaluated, the inclusion of the photo-plethysmograph data channel, or a combination of these factors. The greatest accuracy was obtained by all scorers using the University of Utah chart evaluation rules.
Senter, Stuart M.; Dollins, Andrew B.; Krapohl, Donald J.; and Department of Defense Polygraph Institute Research Division, "Comparison of Utah and DoDPI Scoring Accuracy: Equating Veracity Decision Rule, Chart Rule, and Number of Data Channels Used" (2000). All U.S. Government Documents (Utah Regional Depository). Paper 141.