Trial reportNutrients2020
Adjusting Haemoglobin Values for Altitude Maximizes Combined Sensitivity and Specificity to Detect Iron Deficiency among Women of Reproductive Age in Johannesburg, South Africa.
Trial report in Nutrients, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
16 citing papers in PubMed, 15 citations in OpenAlex.
- Building knowledge, optimising physical and mental health and setting up healthier life trajectories in South African women (BMJ open · 2022Trial
- Implications of changes in WHO haemoglobin elevation adjustment guidelines on global, regional, and national anaemia burden, 1990-2023: a population-based modelling study.The Lancet. Haematology · 2026Article
- Vitamin A intake and status and associations with iron status, anaemia and birth outcomes of pregnant women in the Free State Province, South Africa: the Nutritional Status of Expectant Mothers and their newborn Infants (NuEMI) study.The British journal of nutrition · 2026Article
- Addressing Anemia in High-Altitude Populations: Global Impact, Prevalence, Challenges, and Potential Solutions.American journal of hematology · 2025Review
- Do We Actually Need a New Scale? Improving Postpartum Depression Screening in Malaysia: A Narrative Literature Review.The Malaysian journal of medical sciences : MJMS · 2025Review
- Iron status, anemia, and birth outcomes among pregnant women in urban Bloemfontein, South Africa: the NuEMI study.BMC pregnancy and childbirth · 2024Article
- Evaluation of the hemoglobin cutoff point for anemia in adult women residents of different altitudinal levels in Peru.PloS one · 2024Article
- Evaluating the Diagnostic Performance of Hemoglobin in the Diagnosis of Iron Deficiency Anemia in High-Altitude Populations: A Scoping Review.International journal of environmental research and public health · 2023Article
- A Cross-Sectional Study of the Associations between Biomarkers of Vitamin D, Iron Status, and Hemoglobin in South African Women of Reproductive Age: the Healthy Life Trajectories Initiative, South Africa.Current developments in nutrition · 2023Article
- Determinants of anaemia among women of reproductive age in South Africa: A Healthy Life Trajectories Initiative (HeLTI).PloS one · 2023Article
- Evaluation of a Text Messaging Intervention to Promote Preconception Micronutrient Supplement Use: Feasibility Study Nested in the Healthy Life Trajectories Initiative Study in South Africa.JMIR formative research · 2022Article
- Relationships between adiposity distribution and metabolic health in preconception women in South Africa.Obesity science & practice · 2022Article
- Barriers and facilitators of micronutrient supplementation among non-pregnant women of reproductive age in Johannesburg, South Africa.PLOS global public health · 2022Article
- Food insecurity, diet quality and body composition: data from the Healthy Life Trajectories Initiative (HeLTI) pilot survey in urban Soweto, South Africa.Public health nutrition · 2021Article
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Corrections and comments
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Authors and funding
6 authors at 2 institutions in 3 countries.
Funding
Abstract
In South Africa, haemoglobin (Hb) is measured to screen for iron deficiency (ID). However, low levels of Hb are only a late stage indicator of ID. Furthermore, Hb values are generally not adjusted for altitude even though recommended by WHO. We determined the Hb threshold with the highest combined sensitivity and specificity for detecting ID among South African women living at 1700 m above sea level. In a cross-sectional study of 492 18-25-year-old women, we measured Hb and iron status biomarkers. Using receiver operating characteristic curves, we determined the Hb threshold with maximum Youden Index for detecting ID. This threshold of <12.35 g/dL resulted in a 37.2% anaemia prevalence (20.9% IDA), and sensitivity and specificity of 55.7% and 73.9%, respectively. The WHO altitude-adjusted threshold of <12.5 g/dL resulted in a 39% anaemia prevalence (21.3% IDA), and sensitivity and specificity of 56.8% and 70.8%, respectively. In contrast, using the unadjusted Hb cut-off of <12 g/dL resulted in a 18.5% anaemia prevalence (12.6% IDA), and sensitivity and specificity of 35.1% and 88.6%, respectively. In this sample of South African women of reproductive age an Hb threshold <12.35 g/dL had the highest combined sensitivity and specificity for detecting ID. The diagnostic performance of this Receiver operating characteristic curve-determined threshold was comparable to the altitude-adjusted threshold proposed by WHO. Thus, clinical and public health practice in South Africa should adopt adjustment of Hb for altitude to avoid underestimation of ID and missing women in need for intervention.
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