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Volunteer bias in twin research: The rule of two‐thirds

Lykken, D. T., Tellegen, A., DeRubeis, R.·1978·Social Biology

Abstract

Studies of adult same‐sex twins which rely upon volunteer subjects typically consist of about two‐thirds female and two‐thirds monozygotic (MZ) pairs. Because of this recruitment bias, the male and dizygotic (DZ) twins in such studies will be less representative of their respective populations and will show smaller between‐pair variance on many traits than will the comparison samples of female and MZ twins. This reduction in between‐pair variance results in underestimation of the true intraclass correlation in the populations of DZ twins and in overestimation of the true heritability of the trait under study. The only adequate solution to this problem may be to provide sufficient extrinsic incentive (e.g., money payments) to overcome the strong recruitment bias documented in this paper.

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Metadata

Authors
Lykken, D. T., Tellegen, A., & DeRubeis, R.
Venue
Social Biology
Published
1978-03
Volume
25
Issue
1
Pages
1-9
ISSN
0037-766X (ISSN-L)
OpenAlex
W1976293919
Cited by
214
References
0
FWCI
3.15
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Volunteer bias in twin research: The rule of two‐thirds. https://app.cochat.ai/papers/10.1080/19485565.1978.9988312
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Lykken, D. T., Tellegen, A., & DeRubeis, R. (1978). Volunteer bias in twin research: The rule of two‐thirds. Social Biology. https://doi.org/10.1080/19485565.1978.9988312

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