The DOI matches its Crossref record; 26 of the 26 references it cites were found in a registry or an index.
Biological versus nonbiological older brothers and men’s sexual orientation
Open accessAbstract
The most consistent biodemographic correlate of sexual orientation in men is the number of older brothers (fraternal birth order). The mechanism underlying this effect remains unknown. In this article, I provide a direct test pitting prenatal against postnatal (e.g., social/rearing) mechanisms. Four samples of homosexual and heterosexual men (total n = 944), including one sample of men raised in nonbiological and blended families (e.g., raised with half- or step-siblings or as adoptees) were studied. Only biological older brothers, and not any other sibling characteristic, including nonbiological older brothers, predicted men’s sexual orientation, regardless of the amount of time reared with these siblings. These results strongly suggest a prenatal origin to the fraternal birth-order effect.
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“The conclusions appear to be based on a comparison of significance (for the coefficient of the number of older brothers) with nonsignificance (for the other coefficients), even though the differences between the coefficients do not appear to be statistically significant.”
From The Difference Between “Significant” and “Not Significant” is not Itself Statistically Significant (2006) · cites this paper as Bogaert (2006)
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Citations
Cites
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Cited by
The Difference Between “Significant” and “Not Significant” is not Itself Statistically Significant
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Neurotoxic autoantibodies mediate congenital cortical impairment of offspring in maternal lupus
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Metadata
- Authors
- Bogaert, A. F.
- Affiliations
- Brock University (CA)
- Corresponding author
- Bogaert, Anthony F.
- ORCID
- Bogaert, Anthony F.
- Venue
- Proceedings of the National Academy of Sciences
- Publisher
- National Academy of Sciences
- Published
- 2006-07-11
- Volume
- 103
- Issue
- 28
- Pages
- 10771-10774
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- PMC
- PMC1502306
- OpenAlex
- W2137113462
- Cited by
- 238
- References
- 26
- Citations by year
- 2026: 7 · 2025: 4 · 2024: 3 · 2023: 14 · 2022: 10 · 2021: 6 · 2020: 76 · 2019: 5 · 2018: 6 · 2017: 11 · 2016: 10 · 2015: 10 · 2014: 10 · 2013: 13 · 2012: 5
- FWCI
- 4.22
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Proceedings of the National Academy of Sciences (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Johns Hopkins University
- Social Sciences and Humanities Research Council of Canada
- Topics
- Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Sexual Differentiation and Disorders
- Social Sciences › Psychology › Social Psychology › LGBTQ Health, Identity, and Policy
- Social Sciences › Gender Studies › Gender and Feminist Studies
- Keywords
- sexual orientation, older brothers, biological siblings, adopted children, stepfamilies, prenatal origin, gay men, heterosexual men
- MeSH terms
- Adoption, Birth Order, Female, Humans, Male, Predictive Value of Tests, Sexual Behavior, Homosexuality, Male, Siblings
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
