Trial reportEnvironmental health perspectives2022
Portable HEPA Filter Air Cleaner Use during Pregnancy and Children's Cognitive Performance at Four Years of Age: The UGAAR Randomized Controlled Trial.
Trial report in Environmental health perspectives, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
11 citing papers in PubMed.
- Analysis of sources and sinks of indoor particulate matter reveals insights into the real-world efficacy of portable air cleaners in a randomized intervention trial.The Science of the total environment · 2025Trial
- Health Benefits of Air Purification: A Systematic Review.Environment & health (Washington, D.C.) · 2026Review
- Cognitive benefits of air purification among schoolchildren: A randomized, double-blind, crossover trial.Innovation (Cambridge (Mass.)) · 2026Article
- Performance of quantile regression methods with discrete outcomes: A simulation study with applications to environmental epidemiology.Environmental epidemiology (Philadelphia, Pa.) · 2025Article
- Mapping multilevel adaptation response to protect maternal and child health from climate change impacts: A scoping review.iScience · 2025Review
- Interventions to reduce the effects of air pollution and of extreme heat on maternal, newborn, and child health outcomes: a mapping of the literature.Journal of global health · 2025Review
- Assessing the association between household air pollution exposure and child heath in Mongolia: a birth-cohort study.Scientific reports · 2025Article
- Effect of high-efficiency particulate air filter on children with asthma: a systematic review protocol of RCTs.BMJ open · 2024Article
- Sensitivity analysis for live birth bias in the Ulaanbaatar Gestation and Air Pollution Research study.Environmental epidemiology (Philadelphia, Pa.) · 2022Article
- Invited Perspective: HEPA Filters-An Effective Way to Prevent Adverse Air Pollution Effects on Neurodevelopment?Environmental health perspectives · 2022Article
- Gestational and early childhood air pollution exposure and neurodevelopmental outcomes in early childhood.Neurotoxicology and teratologyArticle
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Authors and funding
11 authors.
Funding
Abstract
backgroundDevelopmental exposure to air pollution is associated with diminished cognitive abilities in observational studies, but no randomized controlled trial has examined the effect of reducing air pollution on cognition in children.
objectivesWe sought to quantify the impact of reducing exposure to particulate matter (PM) during pregnancy on children's cognitive performance at 4 y of age.
methodsIn this single-blind, parallel-group, randomized controlled trial in Ulaanbaatar, Mongolia, we randomly assigned 540 nonsmoking pregnant women (268 intervention and 272 control) to receive 1-2 portable high-efficiency particulate air (HEPA) filter air cleaners or no air cleaners. The air cleaners were used from a median of 11 wk gestation until the end of pregnancy. The primary outcome was full-scale intelligence quotient (FSIQ) assessed using the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) when children were a median of 48 months old. We imputed missing outcome data using multiple imputation with chained equations, and our primary analysis was by intention to treat.
resultsAfter excluding known miscarriages, stillbirths, neonatal deaths, and medical conditions that impeded cognitive testing and imputation, 475 (233 control and 242 intervention) children were included in our analyses. In an unadjusted analysis, the mean FSIQ of children who were randomly assigned to the intervention group was 2.5 points [95% confidence interval (CI):
conclusionsReducing PM air pollution during pregnancy may improve cognitive performance in childhood. https://doi.org/10.1289/EHP10302.
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