key: cord-0814350-56fctszn
authors: Tandaju, Jeremy Rafael; Ii, Wang; Barati-Boldaji, Reza; Raeisi-Dehkordi, Hamidreza
title: Meta-analysis of statin and outcomes of coronavirus disease 2019 (COVID-19): reconsideration is needed
date: 2021-07-05
journal: Nutr Metab Cardiovasc Dis
DOI: 10.1016/j.numecd.2021.06.009
sha: 3b2e6d18ced91608d68b1eafbcf093fa1491b896
doc_id: 814350
cord_uid: 56fctszn

nan

Meta-analysis is a popular approach to introduce novel findings by doing quantitative and 33 qualitative analysis of established studies. However, meta-analysis is subject to biases and 34 mistakes (1). Self-plagiarism or plagiarism and salami publication can be less apparent in meta- 35 analyses, unlike other research, and may be easily missed. 36 In this letter, we would like to discuss an issue of methodological fallacies, potential self- There are several points deserved to be pointed out. First of all, we would like to address the self- 43 plagiarism, text-recycling, and salami publication which is an unfair practice.

Both mentioned articles (2, 3) have the same conclusion on the same topic. Surprisingly, the 45 authors did not cite or mention that the current study is an updated meta-analysis, which may affect of each systematic review, but also decreases the authors' biases (4). 55 We were surprised that the authors self-cited some of their irrelevant publications such as anemia, 56 thyroid, and dementia papers but did not cite the most important one (3). It seems reasonable to 57 update the meta-analysis in case you may face with adequate number of studies which 58 subsequently may affect the conclusion. In addition, the search date between the first and second 59 publications was only 3 months, Thus, there is inadequate justification for updating the review. Reusing data, methodological approach, and ideas to answer the same question with same answer 65 without referring/citing and providing adequate explanation can be considered as text-recycling 66 and self-plagiarism. Omitting analysis so that it can be written as another paper is a salami 67 publication (5).

As another major point, we would also like to ask for clarification in the methodological fallacies 69 presented by the authors. 

Our next concern relates to the extent to which the risk of bias assessment was explained.

Elaborating the justifications behind the judgments of risk of bias not only provides clear 110 transparency, but also helps reviewers/readers to decide whether they agree with the judgements 111 or not (15), according to the Cochrane Collaboration. This matter is of great importance, 112 considering that risk of bias often threatens the validity of meta-analyses results.

Based on the above mentioned points. We would like to ask the authors to provide clarification on 114 these issues. We also urge editors to re-evaluate the papers for fallacy, mistakes, and unethical 115 practices. If academic misconduct or flaws are found, necessary action(s) should be taken to state 116 the commitment towards academic integrity and honesty. We are afraid that, if these things keep 117 on going and disciplinary actions are not taken, there will be more biases, fallacies, and unethical 118 practices done by other researchers in the future because such things can be done without 119 consequences. 120 We hope that this letter could be taken into consideration and bring more clear future towards 121 research in the field of medicine.

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