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Volunteer bias
A selection bias caused when people who opt in differ systematically from those who do not.
Published 04 August 2026Updated 04 August 2026
Volunteer bias can distort surveys and studies because willingness to participate may be related to interest, experience, health, time, or strong opinions. Compare volunteers with the target population and use recruitment methods that reduce self-selection.
Cognitive BiasEvidenceResearch Methods
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