ArticleThe Journal of clinical endocrinology and metabolism2013
Variability and reproducibility of circulating vitamin D in a nationwide U.S. population.
Article in The Journal of clinical endocrinology and metabolism, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 34 papers, 2 of them syntheses that pooled it.
What it found
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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.
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.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
34 citing papers in PubMed, 2 syntheses or guidelines pooled it, 54 citations in OpenAlex.
- Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health.The Cochrane database of systematic reviews · 2020Pooled it
- Serum 25-hydoxyvitamin D concentrations in relation to Hashimoto's thyroiditis: a systematic review, meta-analysis and meta-regression of observational studies.European journal of nutrition · 2020Pooled it
- Circulating Vitamin D Levels and Risk of Colorectal Cancer in Women.Cancer prevention research (Philadelphia, Pa.) · 2015Trial
- Exploring Vitamin D Trends Through Big Data Analysis.Nutrients · 2025Article
- Ambient air pollution in critical windows of exposure and spontaneous miscarriage in a preconception cohort.Environmental research · 2025Article
- Longitudinal Stability of Vitamin D Status and Its Association With Bone Mineral Density in Middle-aged Australians.Journal of the Endocrine Society · 2022Article
- Vitamin D status is heritable and under environment-dependent selection in the wild.Molecular ecology · 2022Article
- Recognized and Emerging Features of Erythropoietic and X-Linked Protoporphyria.Diagnostics (Basel, Switzerland) · 2022Review
- Pre-infection 25-hydroxyvitamin D3 levels and association with severity of COVID-19 illness.PloS one · 2022Article
- Tracking of serum 25-hydroxyvitamin D during 21 years.European journal of clinical nutrition · 2021Article
- Article
- Determinants of vitamin D status in Kenyan calves.Scientific reports · 2020Article
- Association between vitamin D metabolites, vitamin D binding protein, and proteinuria in dogs.Journal of veterinary internal medicine · 2020Article
- Nutrients and Porphyria: An Intriguing Crosstalk.International journal of molecular sciences · 2020Review
- Maternal vitamin D status during pregnancy and offspring risk of childhood/adolescent depression: Results from the Avon Longitudinal Study of Parents and Children (ALSPAC).Journal of affective disorders · 2020Article
- Vitamin D and Reproductive Hormones Across the Menstrual Cycle.Human reproduction (Oxford, England) · 2020Article
- Vitamin D Practice Patterns in National Collegiate Athletic Association Division I Collegiate Athletics Programs.Journal of athletic training · 2020Article
- Observational
- Associations between vitamin D levels and polycystic ovary syndrome phenotypes.Minerva endocrinologica · 2019Article
- Associations between vitamin D and pulmonary function in chronic spinal cord injury.The journal of spinal cord medicine · 2019Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors at 4 institutions in 1 country.
Funding
Abstract
contextMost studies examining associations between circulating vitamin D and disease are based on a single measure of vitamin D, which may not reflect levels over time, particularly because vitamin D concentrations vary by season. Few studies evaluated how well multiple 25-hydroxyvitamin D [25(OH)D] measures track within the same individual over time.
objectiveThis study examined variability and reproducibility of vitamin D by evaluating repeat measurements of plasma 25(OH)D concentrations while accounting for determinants of circulating concentrations including dietary supplement use and latitude of residence from a population of U.S. radiologic technologists. DESIGN AND
participantsWe analyzed circulating 25(OH)D in blood samples taken from 538 men and women from a prospective, nationwide study at two time points within a 1-yr period, most measured in different seasons. Inter- and intra-individual variability, reliability coefficients, and measurement error were examined.
resultsThe spearman rank correlation between two measurements of 25(OH)D concentrations was moderate (r = 0.75, P < 0.001) and did not vary significantly by participant characteristics including age, race, or latitude. The intraclass correlation coefficient was 0.72 (95% confidence interval = 0.68-0.76). The deattenuation factor of plasma 25(OH)D levels was 1.39, suggesting that a single measure of vitamin D on a continuous scale in regression analyses may result in attenuated relationships of about 40%.
conclusionOur results suggest that a single blood sample obtained in spring or fall provides a reasonable average for 25(OH)D over a 1-yr period, but additional studies are needed to estimate variability and agreement in plasma 25(OH)D measurements over longer intervals and younger populations.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.