Polygraph Glossary Practice

comparative response question

Definition

The comparative response question is the original name given by John Reid in 1947 for what would later be called the control question and ultimately the Comparison Question. It was a probable-lie question designed to elicit responses for comparison against relevant question responses.

What Is a Comparative Response Question?

A comparative response question is an alternative term for a comparison question — a question used in Comparison Question Technique (CQT) formats to provide a physiological reference point against which responses to relevant questions are compared. The term emphasises the question's functional role: it generates a comparative physiological response that serves as the control in the within-subject comparison that is fundamental to CQT scoring.

Function in CQT Formats

The comparative response question addresses a broader behavioural topic than the specific issue under investigation. Under psychological set theory, truthful examinees allocate greater physiological arousal to these questions (because they represent their primary area of concern), while deceptive examinees allocate greater arousal to the relevant questions. This differential pattern is quantified through numerical scoring at each analysis spot.

Types of Comparative Response Questions

Comparative response questions come in several forms, each associated with different validated techniques:

Probable-lie comparison questions — Questions designed so that the examinee is likely to be somewhat deceptive in their answer (used in Utah PLT and Backster ZCT)
Directed-lie comparison questions — Questions where the examinee is explicitly instructed to lie (used in DLT and DLST formats)
Current exclusive comparison questions — Comparison questions limited to a specific current time period

Terminology Note

The terms "comparative response question," "comparison question," and the older term "control question" all refer to the same functional element. The evolution from "control" to "comparison" reflects a more accurate description of the question's purpose — it provides a physiological comparison point, not a scientific control in the experimental design sense. Different textbooks and examiners may use any of these terms interchangeably.

Cross-references

More practice terms in this glossary

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