TY - JOUR AU - Zimorovat, Alireza AU - Mohammadi-Sartang, Mohsen AU - Barati-Boldaji, Reza AU - Raeisi-Dehkordi, Hamidreza PY - 2021 DA - 2021/03/19 TI - Meta-analysis of vitamin D supplementation and hemoglobin concentration: methodological faults obscure the interpretation of the data JO - Nutrition Journal SP - 22 VL - 20 IS - 1 AB - 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. SN - 1475-2891 UR - https://doi.org/10.1186/s12937-021-00681-w DO - 10.1186/s12937-021-00681-w ID - Zimorovat2021 ER -