A Field Study on the Validity of the Quadri-Track Zone Comparison Technique

by Tuvia Shurany, Einat Stein, Eytan Brand


This field research study comprises the third independent published field study on the validity of the Quadri-Track Zone Comparison Technique (ZCT) initially developed by James Allan Matte in 1977. This study tested and demonstrated the validity and reliability of the Quadri-Track ZC T designed for specific-issue Psychophysiological Veracity (PV) examinations using the polygraph, using fifty-seven confirmed real-life cases from the Liecatcher and Polygraph Center, Thailand, consisting of 26 men and 31 women. Four polygraphists, all formally trained in the use of the Quadri-Track ZCT participated in this field study that examined 4 Israelis, 42 Thais, 4 Chinese, 2 Columbians, 1 American, 1 Vietnamese, 1 Burmese, 1 Englishman, and 1 Australian, indicative of a multi-cultural application of the Quadri-Track ZCT. Lafayette LX 4000 computerized polygraph systems were used in this study. This study indicates that the Quadri-Track ZCT’s unique Inside Track accurately identifies and remedies the major cause (Fear/Hope of Error) of false Positives/Negatives and Inconclusives in Single-Issue tests. The Inside Track’s Fear/Hope of Error reduced the Inconclusives for the confirmed Deceptive cases by 71.5% and the confirmed Truthful cases by 31%. The Inside Track further accurately increased the scores for the Deceptive by 41% and the Truthful by 37%, thereby reducing the overall inconclusive rate from 50.8% to 0%. The Quadri-Track ZCT correctly identified 100% of the Innocent as Truthful with no Inconclusive and no errors. It further correctly identified 92.9% of the Guilty as Deceptive, with no Inconclusive and a 7.1% error rate. Overall, the Quadri-Track ZCT was 96.5% accurate in the identification of the Innocent and the Guilty. Furthermore, a comparison was made of the results of the Quadri-Track ZCT between the confirmed cases (n. 57) and the unconfirmed cases (n. 108) which revealed no significant difference in the frequency of the three decisions, nor was there any significant difference in the average score per chart for the confirmed and unconfirmed cases, with and without the inside track. Hence the data shows that there is no significant difference in the reactivity or responsiveness of the examinees in the confirmed versus the unconfirmed cases, thus the confirmed cases appear to be a representative sample of the total cases.

About the Authors

Tuvia Shurany is Retired Head of the Polygraph Department at the Israeli Security Agency and a full member of the British Polygraph Association and the American Polygraph Association. He is former Director of the University of Panama International Institute for Polygraph Training, Panama, and currently Director of the polygraph unit of G4S Costa Rica. He is also President of Liecatcher Polygraph Services, Israel.

Dr. Einat Stein is a faculty member at the Department of Psychology, Bar Llan University, Israel.

Eytan Brand is a retired officer of the Israeli Security Agency and currently an associate at Liecatcher Polygraph Services, Israel.

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The full study was published in published in European Polygraph, Journal of Andrze Frycz Modrzewski Krakow University, Poland, Volume 1, Number 1(7) 2009.
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