Polygraph Glossary Technique

Single-Issue Test

Also known as — Specific-Issue / Diagnostic Test

Definition

A polygraph examination that focuses on one specific target issue or event (e.g., "Did you steal the money on March 15th?"). Considered more accurate than multi-issue screening tests because attention is focused on a single topic. Results are reported as DI, NDI, or INC. All APA-validated diagnostic techniques are single-issue or event-specific formats. Recommended for legal, evidentiary, and investigative applications.

What Is Single-Issue Test?

Single-Issue Test (Specific-Issue / Diagnostic Test) is a polygraph testing technique. A polygraph examination that focuses on one specific target issue or event (e.g., "Did you steal the money on March 15th?"). Considered more accurate than multi-issue screening tests because attention is focused on a single topic. Results are reported as DI, NDI, or INC. All APA-validated diagnostic techniques are single-issue or event-specific formats. Recommended for legal, evidentiary, and investigative applications.

How Single-Issue Test Works in Practice

As a polygraph testing technique, Single-Issue Test follows structured protocols for question presentation and physiological data collection. The technique is used within the broader framework of Psychophysiological Detection of Deception and must be administered by a trained, APA-member examiner following established Standards of Practice.

During a polygraph examination using this approach, the examiner collects physiological data across multiple channels — respiratory, electrodermal, cardiovascular, and movement — while presenting a structured sequence of relevant, comparison, and irrelevant questions. The examinee's differential physiological responses to these question types form the basis for the diagnostic or screening opinion.

Scoring and Data Analysis

Results from examinations using this technique are analysed using validated Test Data Analysis methods. These include manual numerical scoring systems (3-position or 7-position scales) and automated computerised scoring algorithms such as OSS-3, PolyScore, or ESS. The choice of scoring method affects the balance between sensitivity (detecting deception) and specificity (confirming truthfulness), as well as the inconclusive rate.

Related Terms

Understanding Single-Issue Test in context requires familiarity with several related polygraph concepts:

Key Takeaways

Single-Issue Test is an important concept within the field of Psychophysiological Detection of Deception. Whether you are a polygraph examiner, student at an APA-accredited training program, legal professional evaluating polygraph evidence, or a private individual preparing for a lie detector test, understanding this term and its relationship to other polygraph concepts will help you navigate the field with greater confidence and knowledge.

The science of polygraph testing has evolved significantly over more than 100 years, from the early work of William Moulton Marston and Leonarde Keeler to today's digital instruments and validated scoring algorithms. Every term in this glossary represents a piece of that scientific and professional heritage. For a comprehensive overview, visit the Polygraph Examiner Hub or use our examiner selection guide to find a professional examiner near you.

Cross-references

More technique terms in this glossary

confirmatory testing Confirmatory testing is a PDD examination used to verify the statements of witnesses, victims, or confidential source... inside track The inside track is one of three tracks in the Quadri-Track Zone Comparison Technique. It contains two questions: one... inter-chart stimulation Inter-chart stimulation is the examiner-examinee interaction occurring between individual test charts. It may include... Computer Assisted Polygraph System The Computer Assisted Polygraph System (CAPS) was developed by David Raskin and John Kircher at the University of Uta... silent answer test The silent answer test (SAT) directs examinees to answer internally rather than verbally, avoiding respiratory distor... Silent Talker Silent Talker is an experimental automated credibility assessment system that analyses body movements and facial gest...

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