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Cited by 256

The DOI matches its Crossref record; 41 of the 41 references it cites were found in a registry or an index.

Bias from conditioning on live birth in pregnancy cohorts: an illustration based on neurodevelopment in children after prenatal exposure to organic pollutants

Open access
Liew, Zeyan, Olsen, Jørn, Cui, Xin, Ritz, Beate, Arah, Onyebuchi A·2015·International Journal of Epidemiology

Abstract

Only 60-70% of fertilized eggs may result in a live birth, and very early fetal loss mainly goes unnoticed. Outcomes that can only be ascertained in live-born children will be missing for those who do not survive till birth. In this article, we illustrate a common bias structure (leading to 'live-birth bias') that arises from studying the effects of prenatal exposure to environmental factors on long-term health outcomes among live births only in pregnancy cohorts. To illustrate this we used prenatal exposure to perfluoroalkyl substances (PFAS) and attention-deficit/hyperactivity disorder (ADHD) in school-aged children as an example. PFAS are persistent organic pollutants that may impact human fecundity and be toxic for neurodevelopment. We simulated several hypothetical scenarios based on characteristics from the Danish National Birth Cohort and found that a weak inverse association may appear even if PFAS do not cause ADHD but have a considerable effect on fetal survival. The magnitude of the negative bias was generally small, and adjusting for common causes of the outcome and fetal loss can reduce the bias. Our example highlights the need to identify the determinants of pregnancy loss and the importance of quantifying bias arising from conditioning on live birth in observational studies.

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Metadata

Authors
Liew, Z., Olsen, J., Cui, X., Ritz, B., & Arah, O. A.
Venue
International Journal of Epidemiology
Published
2015-01-19
Volume
44
Issue
1
Pages
345-354
ISSN
  • 0300-5771 (ISSN-L)
  • 1464-3685
OpenAlex
W2112721631
Cited by
256
References
41
FWCI
14.89
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Bias from conditioning on live birth in pregnancy cohorts: an illustration based on neurodevelopment in children after prenatal exposure to organic pollutants. https://app.cochat.ai/papers/10.1093/ije/dyu249
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Liew, Z., Olsen, J., Cui, X., Ritz, B., & Arah, O. A. (2015). Bias from conditioning on live birth in pregnancy cohorts: an illustration based on neurodevelopment in children after prenatal exposure to organic pollutants. International Journal of Epidemiology. https://doi.org/10.1093/ije/dyu249

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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.