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 Table of Contents  
Year : 2022  |  Volume : 8  |  Issue : 2  |  Page : 95-98

The malady of redundant publications: Common yet poorly understood

1 Department of Anatomy, Pondicherry Institute of Medical Sciences, Puducherry, India
2 Department of Pharmacology, Pondicherry Institute of Medical Sciences, Puducherry, India

Date of Submission12-Oct-2022
Date of Decision01-Nov-2022
Date of Acceptance04-Nov-2022
Date of Web Publication23-Dec-2022

Correspondence Address:
Aparna Muraleedharan
Department of Anatomy, Pondicherry Institute of Medical Sciences, Puducherry
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jcrsm.jcrsm_85_22

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How to cite this article:
Muraleedharan A, Kumar B A. The malady of redundant publications: Common yet poorly understood. J Curr Res Sci Med 2022;8:95-8

How to cite this URL:
Muraleedharan A, Kumar B A. The malady of redundant publications: Common yet poorly understood. J Curr Res Sci Med [serial online] 2022 [cited 2023 May 30];8:95-8. Available from: https://www.jcrsmed.org/text.asp?2022/8/2/95/364507

The research process involves framing the research question and objectives, designing an appropriate methodology to address them, data collection, data analysis, and writing up the paper to disseminate the study findings as a publication. An institutional ethics committee usually takes care of the ethical aspects of a study's planning and execution. In contrast, ethical considerations are less understood and monitored during the publication stage. Publication ethics is a gray area for many researchers. The Committee on Publication Ethics (COPE)[1] specifies the “code of conduct” and “best practice guidelines” in the publication process. It provides recommendations for journal editors on how to handle cases of research and publication misconduct, when detected.

Publication misconduct is recently gaining importance. Publishers and editors are paying attention to this increasing problem, but many authors remain unaware of ethical guidelines related to publishing. Publication misconduct is of several types: duplicate publication, simultaneous publication, excess self-citation, salami slicing, redundant publication (RP), plagiarism, falsification, and fabrication. It can happen incidentally or intentionally. Plagiarism has already been identified as a major scientific misconduct, and there are several ways of detecting, measuring, and dealing with it. The current editorial is intended to create awareness among authors and readers about what is a RP, why it is a problem, what its consequences are, and what are ways to avoid it.

  What are Redundant Publications? Top

RP refer to those scholarly works where most of the content is used by the same or similar set of authors without proper disclosure or cross-referencing of the primary publication.[2],[3] RP have been described in various broad specialties and super specialties.[4],[5],[6]

  Why Do Researchers Engage in Redundant Publications? Top

The “publish or perish” culture may drive researchers to indulge in unethical practices for career advancements, securing tenured faculty positions, and obtaining research grants; for all of these, the number of peer-reviewed publications is seen as a key indicator of academic productivity.[7],[8],[9] RP may happen due to several reasons; some possible scenarios are described below:

A postgraduate or research scholar publishing papers from his dissertation

After completing a dissertation, a postgraduate or research scholar, often with the encouragement of a guide/supervisory person, publishes more than one article based on the dissertation.

A researcher reporting on a longitudinal/follow-up study

A researcher involved in a longitudinal study reports the findings in multiple articles. As long as each article contains new information, the articles are not considered RP. However, it is the author's responsibility to describe how a subsequent manuscript extends the knowledge and differs from previous work. As an example, the much-cited Madras Longitudinal Study of First-episode Schizophrenia has yielded multiple publications based on course and outcomes data, from the same cohort, at different time points of follow-up.[10] If the findings are not sufficiently different at two follow-up points, then the two papers may be considered redundant due to significant overlap.

Author prepares multiple papers from a large study having multiple objectives

Studies with multiple, unrelated objectives can be published independently. In contrast, if the objectives are related, it will be considered a RP. In other words, if a study deals with two unrelated hypotheses, it is not considered unethical to publish them separately. There are gray areas here, and when in doubt, authors would be well-advised to discuss the appropriate course of action with a sufficiently experienced senior academic. However, in so far as postgraduate dissertations are concerned, more often than not, publishing each objective as a separate paper will be a redundant exercise.

For example: A postgraduate student does a randomized control trial with one primary and three secondary objectives. He chooses to publish each objective as a separate paper, thus generating four publications from a single study. The sample size would have been estimated based on the primary objective, and hence the other three papers will not have adequate statistical power. In such cases, the publication of separate papers based on secondary objectives will be deemed redundant. Instead, the right approach is to present all study objectives (primary and secondary) in a single paper and acknowledge the findings pertaining to secondary objectives as preliminary and requiring further validation.

  What are the Types of Redundant Publications? Top

Redundant publications are of several types[5],[6]

Dual or duplicate publications

Dual or duplicate publications are papers where the same set of authors publishes more or less similar findings from the same study/dataset as two or more separate papers in the same or different journals. The results and conclusions of the publications are highly similar. For example, a researcher submits a paper reporting the impact of add-on (drug) X therapy on hyperlipidaemia in patients with diabetes mellitus and another paper reporting the effect of add-on (drug) X therapy on serum lipid levels in patients on oral hypoglycaemic agents. This should raise suspicion of a dual publication. If both papers are submitted at the same time to two different journals, it is considered simultaneous publications.

Suspected dual publications

Suspected dual publications are papers where the authors publish more or less similar findings from a slightly different dataset with minor additions (<50%), probably as a part of a follow-up study, as two or more separate papers in the same or different journals. The results and conclusions of the publications are highly similar. For example, a researcher studying the effect of drug Y on insomnia in elderly patients publishes a paper reporting the impact of the drug on sleep duration and sleep quality in 150 patients in a journal and later submits a paper reporting the impact of the same drug on sleep duration and sleep quality in 200 patients. The titles of the papers are different, and the authors are slightly different or the same with a different author order, but the results and conclusions are highly similar. This is considered a suspected dual submission.

Salami slicing

Salami slicing is the most common type of RP.[4] Salami slicing means producing multiple publications from a single study/dataset. Here, the researcher splits the study data into the smallest possible publishable units or “slices” to increase the volume of his/her publications, and he may or may not realize that it is unethical to do so. This usually happens as a result of research that involves multiple related objectives. If there is more than one publication from the same study with two unrelated hypotheses, it is not considered as salami slicing. However, the hypothesis tested in each paper must be specified. Often, longitudinal data with several outcome measures may be published independently, but the authors must ensure minimal overlap with published results, and they should also mention the original source. Merely citing the previous work in the bibliography does not suffice. If each “slice” tests a different hypothesis, has a different methodology, or studies different populations, it is acceptable to publish it separately. A good example would be large epidemiological trials where multiple research questions are sought to be addressed simultaneously. The Framingham Heart Study, a population-based prospective observational cohort study, is a classic example.[11] Multiple publications based on findings at different time points, from different sub-cohorts, detailed basic methodology, and demographic details are considered legitimate. Hence, labeling a publication as salami slicing needs to be considered on a case-by-case basis. Blanket recommendations are difficult.[12] Publishing several articles from the same dataset with a related hypothesis is considered “salami slicing” and is taken as RP, which is unethical.

Meat extender publications

Meat extender publications are more or less the same as suspected dual publications; the major difference is that the results and conclusions of the publications are different. Here, the same set of authors publishes more than one paper from a slightly different dataset where minor additions (<50%) have been added probably as a part of a follow-up study, as two or more separate papers in the same or different journals.[4] For example, a researcher studying the effect of drug Y on insomnia in elderly patients publishes a paper reporting the impact of the drug on sleep duration and sleep quality in 150 patients in a journal and later submits a paper reporting the impact of the drug on morning waking time in 200 patients. The second paper is considered as a meat extender, as a part of the dataset of second paper is already included in the first paper though the results and conclusions may appear seemingly different.

  What are the Scientific and Ethical Issues Associated With Redundant Publication? Top

Breaking copyright laws

Once an article has been published in a journal, the authors transfer the copyright of the article to the journal. Duplication of the data or material is a violation of copyright laws.[3]

Bias results of meta-analysis

Meta-analysis and systematic reviews form the highest level of scientific evidence. Results of published literature are combined using statistical methods. When the results of the same study are duplicated in more than one publication, all of them are taken into analysis. This results in skewed results as the same patients get counted more than once.[13]

Scientific junk increases

The readers and authors have to sift through mounds of redundant literature before arriving at a relevant article of interest to them. The major problem that journal editors face these days is difficulty in getting peer reviewers. A lot of peer reviewer and editorial time gets wasted on handling redundant manuscripts. A large number of institutional grants and sponsorships are also used as article processing charges for these RP.[14]

Academic misuse

Academic quality is decided by the quantity and quality of research publications and is used to get research grants, appointments, career advancement, and promotions. To embellish their chances of obtaining tenured positions and research grants, academics may resort to RP.[8]

  How to Root Out the Menace of the Practice of Redundant Publications? Top

There are organizations that give suggestions and guidelines to assist authors, editors, and reviewers in best practices of scientific publishing, including RP. The purpose of these organizations is to create and disseminate research publications in an ethical manner. International Committee of Medical Journals Editors,[15] World Association of Medical Editors,[16] and COPE deal with ethical aspects related to the publication process.[17] COPE suggests practical ways to deal with publication and research misconduct and has also set codes of conduct for good publication practice. COPE provides clear guidelines for handling RP before and after the publication process.[18]

  Responsibility of Authors Top

All authors must follow the rules of good scientific publication practice and stick to their responsibility of truthfully declaring if the whole or part of their research work has been published priorly to prevent RP. When in doubt, young authors are advised to consult seniors or appropriate authorities who can guide them correctly regarding publication ethics. Authors must look at the study datasets as a whole, not as small fragments. Slicing data will prevent valuable conclusions that could have been derived if data was looked at as a whole. Fragmenting data has limited value and may end up distorting scientific literature. This will hinder scientific advancement.[17]

  Responsibility of Journal Editors Top

All attempts should be made to detect RP. Excessive self-citation and too much text recycling should be considered as red flag signs. The actions to be taken on the detection of RP are described in the COPE flowchart. When publication misconduct is detected before publication, authors can be informed that their misconduct has been identified and ask them to withdraw the manuscript. If the paper is already published, authors can be provided with an opportunity for self-confession. The article may be retracted, and the institutional head can be informed. The authors can also be blacklisted by the journal. If authors deny their misconduct, editors can take appropriate action as per the COPE guidelines.[2],[3],[19]

  Responsibility of Institutions Top

Institutions should offer training in ethical aspects related to research and publication. Compared to plagiarism and data fabrication which are regarded as major academic crimes, the practice of RP is considered a less serious issue and as a misdemeanour. Nonetheless, academic institutions should have policies on how to deal with it. They should have a research integrity officer and publish their contact details prominently to report any proven misconduct by researchers. In addition, an institutional investigation or disciplinary hearing on research misconduct should recommend retraction or correction of the redundant paper by the researcher.[3],[20]

To conclude, RP are quite common among all medical specialties. It is the joint responsibility of authors, journals, and research institutions to develop ways to prevent this practice which is unethical and can hamper scientific advancement.

  References Top

COPE: Committee on Publication Ethics. Available from: https://publicationethics.org/. [Last accessed on 2022 Oct 11].  Back to cited text no. 1
Kumar AS, Beyersdorf F, Denniss AR, Lazar HL, Patterson GA, Weisel RD. Joint statement on redundant (duplicate) publication by the editors of the undersigned cardio-thoracic journals. Eur J Cardiothorac Surg 2015;48:343.  Back to cited text no. 2
Wager E. Why is redundant publication a problem? Int J Occup Environ Med 2015;6:3-6.  Back to cited text no. 3
Menon V, Varadharajan N, Praharaj SK, Ameen S. Trust but verify: An analysis of redundant publications from two major psychiatry journals in India. Indian J Psychiatry 2022;64:342-8.  Back to cited text no. 4
  [Full text]  
Schein M, Paladugu R. Redundant surgical publications: Tip of the iceberg? Surgery 2001;129:655-61.  Back to cited text no. 5
Rosenthal EL, Masdon JL, Buckman C, Hawn M. Duplicate publications in the otolaryngology literature. Laryngoscope 2003;113:772-4.  Back to cited text no. 6
Aggarwal R, Gogtay N, Kumar R, Sahni P, Indian Association of Medical Journal Editors. The revised guidelines of the medical council of India for academic promotions: Need for a rethink. Indian J Occup Environ Med 2016;20:1-4.  Back to cited text no. 7
[PUBMED]  [Full text]  
Kairouz VF, Raad D, Fudyma J, Curtis AB, Schünemann HJ, Akl EA. Assessment of faculty productivity in academic departments of medicine in the United States: A national survey. BMC Med Educ 2014;14:205.  Back to cited text no. 8
Yank V, Barnes D. Consensus and contention regarding redundant publications in clinical research: Cross-sectional survey of editors and authors. J Med Ethics 2003;29:109-14.  Back to cited text no. 9
Rangaswamy T. Twenty-five years of schizophrenia: The Madras longitudinal study. Indian J Psychiatry 2012;54:134-7.  Back to cited text no. 10
  [Full text]  
Framingham Heart Study (FHS) | NHLBI, NIH. Available from: https://www.nhlbi.nih.gov/science/framingham-heart-study-fhs. [Last accessed on 2022 Oct 11].  Back to cited text no. 11
Menon V, Muraleedharan A. Salami slicing of data sets: What the young researcher needs to know. Indian J Psychol Med 2016;38:577-8.  Back to cited text no. 12
[PUBMED]  [Full text]  
Tramèr MR, Reynolds DJ, Moore RA, McQuay HJ. Impact of covert duplicate publication on meta-analysis: A case study. BMJ 1997;315:635-40.  Back to cited text no. 13
Smart P. Redundant publication and salami slicing: The significance of splitting data. Dev Med Child Neurol 2017;59:775.  Back to cited text no. 14
International Committee of Medical Journal Editors (ICMJE). International Committee of Medical Journal Editors (ICMJE): Uniform requirements for manuscripts submitted to biomedical journals: Writing and editing for biomedical publication. Haematologica 2004;89:264.  Back to cited text no. 15
About Us || WAME. Available from: https://wame.org/aboutus. [Last accessed on 2022 Oct 11].  Back to cited text no. 16
Wager E. The Committee on Publication Ethics (COPE): Objectives and achievements 1997-2012. Presse Med 2012;41:861-6.  Back to cited text no. 17
ICMJE | Recommendations | Overlapping Publications. Available from: https://www.icmje.org/recommendations/browse/publishing-and-editorial-issues/overlapping-publications.html. [Lastaccessed on 2022 Oct 11].  Back to cited text no. 18
Das N. Duplicate publication and the need to strengthen editorial policy of the journal. South Asian J Cancer 2017;6:35-6.  Back to cited text no. 19
[PUBMED]  [Full text]  
Wager E, Kleinert S. Cooperation between research institutions and journals on research integrity cases: Guidance from the Committee on Publication Ethics. Saudi J Anaesth 2012;6:155-60.  Back to cited text no. 20
[PUBMED]  [Full text]  


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