Evidence map›Paper›PMID 39742969›Full record

ArticleThe Journal of nutrition2025

Concordance between Hemoglobin and Hematocrit among Children and Pregnant Persons in National Health and Nutrition Examination Survey Data, 1999-2020.

Maren E Wolf, Maria Elena D Jefferds, Lisa D Gardner, Zuguo Mei, Christine M Pfeiffer, O Yaw Addo

Abstract read
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Article in The Journal of nutrition, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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1citing papers in PubMed
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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Observational
4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Maren E WolfEpidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA, United States; International Micronutrient Malnutrition Prevention and Control Program, Nutrition Branch, Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States.
Maria Elena D JefferdsInternational Micronutrient Malnutrition Prevention and Control Program, Nutrition Branch, Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States.
Lisa D GardnerInternational Micronutrient Malnutrition Prevention and Control Program, Nutrition Branch, Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States.
Zuguo MeiInternational Micronutrient Malnutrition Prevention and Control Program, Nutrition Branch, Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States.
Christine M PfeifferNutritional Biomarkers Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, United States.
O Yaw AddoInternational Micronutrient Malnutrition Prevention and Control Program, Nutrition Branch, Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States. Electronic address: lyu6@cdc.gov.

Funding

Intramural CDC HHS CC999999
6 · The paper itself

Abstract

backgroundHemoglobin and hematocrit are the 2 most common biomarkers used to identify anemia in clinical settings, but their results do not always agree.

objectivesTo examine agreement between hemoglobin and hematocrit in identifying anemia among children aged 1 to <5 y and pregnant persons.

methodsPregnant persons and children aged 1 to <5 y with hemoglobin and hematocrit results from the same whole blood sample in National Health and Nutrition Examination Survey (1999-2020) were included. We used the Centers for Disease Control and Prevention anemia cutoff values for children, pregnancy status, trimester, and smoking adjustments. We examined concordance of anemia, sensitivity, and specificity among those with anemia based on ≥1 test overall and by race/ethnicity, sex, and income level. Cohen's kappa was used to measure concordance.

resultsAnalytic samples included 7052 children and 1437 pregnant persons, of whom 1119 had trimester data. Among children, anemia prevalence was 3.7% [95% confidence interval (CI): 3.1, 4.3] based on hemoglobin and 5.5% (95% CI: 4.7, 6.3) based on hematocrit. Among pregnant persons, anemia prevalence was 7.7% (95% CI: 5.9, 9.5) based on hemoglobin and 12.4% (95% CI: 10.1, 14.6) based on hematocrit. Kappa scores overall and by sociodemographic characteristics ranged from 0.64 to 0.75 (moderate concordance) among children and from 0.53 to 0.78 (weak to moderate concordance) among pregnant persons. Among those with anemia on ≥1 test, 53.5% of children and 61.5% of pregnant persons had anemia based on both tests.

conclusionsWe found substantial discordance between the 2 biomarkers; ∼50% of children and 40% of pregnant women were identified by only 1 of the 2 biomarkers. Because hemoglobin and hematocrit may be used interchangeably in the clinical setting, individuals with anemia may be missed, not receive treatment, and therefore be at higher risk of adverse pregnancy, birth, and developmental outcomes.

Indexed as

AnemiaHemoglobinsAdultBiomarkersChild, PreschoolFemaleHematocritHumansInfantMaleNutrition SurveysPregnancyUnited StatesBiomarkersHemoglobinsanemiachildrenconcordancediscordancehematocrithemoglobinNHANESpregnant

Identifiers

PMID39742969
PMCPMC12448280

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