Different effects for different questions: An illustration using short cervix and the risk of preterm birth.
exposure effect
population attributable effect
preterm birth
short cervix
Journal
International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics
ISSN: 1879-3479
Titre abrégé: Int J Gynaecol Obstet
Pays: United States
ID NLM: 0210174
Informations de publication
Date de publication:
Mar 2023
Mar 2023
Historique:
revised:
05
07
2022
received:
04
11
2021
accepted:
20
07
2022
pubmed:
29
7
2022
medline:
15
2
2023
entrez:
28
7
2022
Statut:
ppublish
Résumé
To illustrate the difference between exposure effects and population attributable effects. We examined the effect of mid-pregnancy short cervical length (<25 mm) on preterm birth using data from a prospective cohort of pregnant women in Lusaka, Zambia. Preterm birth was live birth or stillbirth before 37 weeks of pregnancy. For estimation, we used multivariable regression and parametric g-computation. Among 1409 women included in the analysis, short cervix was rare (2.4%); 13.6% of births were preterm. Exposure effect estimates were large (marginal risk ratio 2.86, 95% confidence interval [CI] 1.80-4.54), indicating that the preterm birth risk was substantially higher among women with a short cervix compared with women without a short cervix. However, the population attributable effect estimates were close to the null (risk ratio 1.06, 95% CI 1.02-1.10), indicating that an intervention to counteract the impact of short cervix on preterm birth would have minimal effect on the population risk of preterm birth. Although authors often refer to "the" effect, there are actually different types of effects, as we have illustrated here. In planning research, it is important to consider which effect to estimate to ensure that the estimate aligns with the research objective.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
842-849Subventions
Organisme : FIC NIH HHS
ID : K01 TW010857
Pays : United States
Informations de copyright
© 2022 International Federation of Gynecology and Obstetrics.
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