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Comment
. 2021 Mar 19;20(1):22.
doi: 10.1186/s12937-021-00681-w.

Meta-analysis of vitamin D supplementation and hemoglobin concentration: methodological faults obscure the interpretation of the data

Alireza Zimorovat  1   2 , Mohsen Mohammadi-Sartang  3 , Reza Barati-Boldaji  3 , Hamidreza Raeisi-Dehkordi  4   5
Affiliations
Comment

Meta-analysis of vitamin D supplementation and hemoglobin concentration: methodological faults obscure the interpretation of the data

Alireza Zimorovat et al. Nutr J. .

Abstract

We read the review by Arabi et al. with great interest which tried to examine the effects of vitamin D supplementation on hemoglobin concentration. It seems that the article suffers from fundamental methodological issues and the conclusions are likely to be erroneous. In this regard, we would like to ask the authors to address the mentioned limitations and to update the analysis in order to provide robust and trustful results. We are concerned that such meta-analyses may lead to the biased findings and conclusions.

Keywords: Anemia; Hemoglobin; Iron status; Letter to the editor; Vitamin D.

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Conflict of interest statement

Neither of the authors declared a conflict of interest.

Comment in

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References

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