Comparison Question Test (CQT)
Overview
The Comparison Question Test (CQT), also known as the Control Question Test, is the most widely used polygraph technique worldwide. It works by comparing physiological responses to crime-relevant questions against responses to broader "comparison" questions designed to be arousing for truthful examinees. Variants include the Zone Comparison Technique (ZCT), the Utah approach, and the Directed Lie Test (DLT).
CQT research has evolved substantially since its origins with John Reid in the 1940s. Modern variants developed by Raskin, Honts, and Kircher at the University of Utah have been validated in both laboratory and field settings. The debate between probable-lie and directed-lie comparison questions remains one of the most active areas of polygraph research.
CQT studies vary in how they establish ground truth (confessions, panel decisions, or judicial outcomes) and which scoring method is used (numerical hand-scoring vs. computerized algorithms like OSS-3 or PolyScore). These methodological choices significantly affect reported accuracy rates.
Research Landscape
All 33 Studies
POLYGRAPH TECHNIQUES OF COMPARISON QUESTIONS: THEORY AND PRACTICE OF RESEARCH, PROSPECTS OF APPLYING
Vadym Barko · NAUKA I PRAVOOKHORONA
Meta-analytic evidence supports CQT accuracy with effect sizes around r = 0.69, with probable-lie questions (r = 0.71) slightly outperforming…
The Primacy Position of the Comparison Question
Carlos Monge · European Polygraph
The study provides analysis of how primacy positioning influences comparison question effectiveness in polygraph examinations.
Fallacies in the estimation of the validity of the Comparison Question Polygraph Test: A reply to Ginton (2020)
Ben-Shakhar, G., Iacono, W.G. · Journal of Investigative Psychology and Offender Profiling
The authors dismiss Ginton's defenses and conclude his paired-examination validity estimates are untrustworthy due to confirmation bias, criterion contamination, and…
From a Rigid Cover to an Elastic One Via a Blanket too Short: An Adaptive Polygraph Approach
Avital Ginton · European Polygraph
The paper advocates for adaptive polygraph approaches that tailor protocols to specific case circumstances and examinee characteristics, similar to personalized…
Basic vs. Applied Psychology perspectives lead to different implications from the same data; reevaluating the impact of prior expectations on polygraph outcomes
Ginton, A. · Social Sciences & Humanities Open
Examiner bias impacts only 3% of total polygraph examinations in real-world conditions, occurring only when charts are objectively inconclusive and…
Essentials of the Relevant Issue Gravity (RIG) Strength: A Theoretical Framework for Understanding the Comparison Question Test (CQT)
Avital Ginton · European Polygraph
The RIG framework reframes CQT theory by emphasizing differential attention binding rather than simple threat perception, with the critical task…
Rebuttal: The CQT Has Scientific Support
Charles Robert Honts; Steven Thurber · Various Publications
Directly addressed Iacono & Ben-Shakhar (2019) criticisms. Analyzed their arguments point-by-point and found them to lack merit. Corroborated contemporary research…
The Polygraph and Lie Detection: A Case Study
Aabad Ayoub, Farwa Rizvi, Saba… · Arab Journal of Forensic Sciences & Forensic Medicine
Polygraph testing successfully identified deception by the victim who confessed after examination, while all suspects were found truthful. The case…
Examining Different Types of Comparison Questions in a Field Study of CQT Polygraph Technique
Avital Ginton · Journal of Investigative Psychology and Offender Profiling, 14(2), 131–149
Field study comparing different types of comparison questions in real criminal investigations. Provided evidence for the practical effectiveness of both…
A Theoretical Analysis of the Directed Lie Question (DLC)
Nathan J. Gordon · European Polygraph
The analysis questions whether the DLC's adoption represents genuine scientific advancement or a problematic simplification driven by political correctness and…
Specific-issue testing techniques
Donald J. Krapohl, Pamela K.… · Fundamentals of Polygraph Practice
The chapter describes three validated comparison question techniques for criminal investigation, with event-specific testing demonstrating aggregated accuracy rates near 89-90%…
Cognitive and Emotional Reactions to Questions in the Comparison Question Test
A. Luke MacNeill, M. T.… · Perceptual and Motor Skills
Innocent participants did not rate comparison questions as more emotionally concerning than relevant questions when using generic questions, directly challenging…
Effect of the Stimulation Test Administered Before and After the First Relevant Chart of the Control Question Test
James Allan Matte · European Polygraph
The research examined how stimulation test timing influences examinee psychological set and physiological response patterns to relevant and comparison questions…
Commentary on: Horvath F, Palmatier JJ. Critique of Horvath‐Palmatier Laboratory Study on Effectiveness of Exclusive v. Non‐Exclusive Control Questions in Polygraph Examination. J Forensic Sci 2008;53(4):889–99
James A. Matte · Journal of Forensic Sciences
Matte raised methodological concerns about cuff pressure settings (40-55 mmHg vs. recommended 90 mmHg), test structure deviations from validated protocols,…
Effect of Habituation to Least Threatening Zone Questions on the Most Threatening Zone Comparison Questions in Psychophysiological Veracity Examinations
James Allan Matte · European Polygraph
62.9% of confirmed deceptive cases showed higher scores in subsequent charts, supporting differential habituation theory where deceptive examinees maintain or…
Personalization and Calibration of the Control Question in the Control Question Test
Jaworski, R. · Journal of Forensic Identification
Individualized control question construction tailored to an examinee's specific background, experiences, and psychological characteristics enhances test validity compared to standardized,…
Psychological Aspects of the Quadri-Track Zone Comparison Technique and Attendant Benefits of its Inside Track
James Allan Matte · European Polygraph
The Inside Track mechanism theoretically addresses the major cause of false positives and inconclusives by quantifying innocent examinees' fear of…
Information Gain of the CQT Over Interpersonal Deception Detection
Charles Robert Honts; William J.… · Polygraph
Used Information Gain analysis to demonstrate CQT provides significant improvement over human deception detection across nearly the complete range of…
Relevant Issue Gravity (RIG) strength – a new concept in PDD that reframes the notion of psychological set and the role of attention in CQT polygraph
Ginton, A. ·
RIG strength represents the intensity of attention directed toward the relevant issue based on internal cognitive and emotional preoccupation rather…
Relevant Issue Gravity (RIG) Strength: A New Concept in PDD
Avital Ginton · Polygraph
Introduced the Relevant Issue Gravity concept, proposing that the psychological weight of relevant questions influences CQT accuracy. Provided a theoretical…
When should the Polygraph Stimulation Number Test be Performed?
Jan Stefan Widacki · European Polygraph
In 63% of deceptive subjects, reactions to critical questions were greater in the control question test administered after the stimulation…
Effective Policing: Understanding How Polygraph Tests Work and Are Used
William George Iacono · Criminal Justice and Behavior
Examined how polygraph tests function in real law enforcement contexts and their practical effectiveness as investigative tools. Found that polygraph’s…
The Quadri-Track Zone Comparison Technique: it's just not science. A critique to Mangan, Armitage, and Adams (2008)
Verschuere, B., Meijer, E., Merckelbach,… · Physiology & Behavior
The critique identified fundamental methodological flaws including confession-based ground truth creating sampling bias, untested theoretical foundations (psychological set), bias against…
Psychological structure and theoretical concept of the Backster Zone Comparison Technique and the Quadri-Track Zone Comparison Technique
Matte, J.A. · Polygraph
The paper articulates fundamental principles showing that the examinee's psychological set must be self-directed without examiner influence, and that comparison…
Positions of truthfully answered controls on control question tests with the polygraph
Cullen, M.C., Bradley, M.T. · Canadian Journal of Behavioural Science
Control questions answered truthfully could effectively differentiate guilty from innocent participants, but only when presented before relevant questions. When relevant…
Is the inference rule of the control question polygraph technique plausible?
Elaad, E. · Psychology, Crime & Law
Police interrogators' judgments supported the CQT inference rule, and field data showed truthful outcomes were more common than critics predicted,…
The Concealed Information Test as a Tool for Investigating Hidden Knowledge of Crime-Relevant Information
Elaad, E. · Journal of Applied Psychology
Police interrogators' judgments supported the CQT inference rule that guilty suspects show greater concern about relevant questions while innocent suspects…
A critical review of the control questions test (CQT)
Ben-Shakhar, G. ·
The CQT was found to lack adequate scientific validation, failing to satisfy major Daubert criteria. Key problems included absence of…
The Role of Comparison Questions in Physiological Detection of Deception
Steven W. Horowitz; John C.… · Psychophysiology
Mock crime study with 120 participants examining comparison question mechanisms. Found comparison questions produced different physiological patterns for innocent vs.…
Heart rate as an index of psychophysiological detection of deception in the guilty person paradigm using the paired control question technique in a field population
Takehiko YAMAMURA, Norihiko SASAKI · Japanese Journal of Physiological Psychology and Psychophysiology
Tonic (baseline) heart rate was significantly elevated in deceptive versus truthful examinees, providing effective discrimination. Phasic heart rate changes to…
Amnesia: Its detection by psychophysiological measures
Michael B. Lynch · Bulletin of the American Academy of Psychiatry and the Law
Personality-disordered patients were found deceptive at a rate of 63%, nearly five times the rate observed in patients with no…
Accuracy of Polygraph Techniques
David C. Raskin; John A.… · Various Publications
Reported polygraph accuracy exceeding .90 using the CQT format. This early quantification helped establish the scientific foundation for modern polygraph…
Psychopathy and detection of deception in a prison population
Raskin, D.C., Hare, R.D. · Psychophysiology
100% of guilty subjects (both psychopaths and nonpsychopaths) were correctly identified using the CQT, with 91% accuracy for innocent subjects.…