How predatory journals leak into PubMed

What is a predatory journal and why does predatory publishing matter?

There is no clear consensus definition for predatory publishers and journals. Such journals have been referred to as “low quality, amateurish, and often unethical academic publishing that is usually Open Access (OA).”4 Although the descriptor “predatory” has been criticized,5 it is now widely recognized and accepted. The term was introduced by librarian Jeffrey Beall6 who also created and maintained updated blacklists of potential predatory publishers and journals, which were acclaimed by many for their utility in helping scholars to spot fraudulent journals until they were removed in January 2017 for undisclosed reasons.7 Recently, there has been a move to favour identification based on potentially predatory publishing practices.8 In this regard, a set of evidence-based salient features of journals suspected to be predatory has been proposed; these features are straightforward to assess (Box 1).9 A recent commentary identified potential characteristics of predatory journals related to categories such as journal operations, editorial and peer review, manner of communication with authors, article processing charges, and ways of dissemination, indexing and archiving.10 Along with the development of general criteria to discern legitimate from predatory operations, the scientific community has shown an increasing demand for whitelists of journals, because it seems more feasible to evaluate journals objectively based on what they do rather than what they do not do. The Directory of Open Access Journals is widely considered the most comprehensive whitelist of open-access journals deemed to be reputable.11 Yet, adequate quality control of journal whitelists remains a problem.12

Most predatory journals are active in the biomedical sphere.13 Predatory publishing practices allow bad research that is poorly peer-reviewed, or published without peer review, to be published alongside real science that is rigorously reviewed, thus obscuring scientific truth.14 Furthermore, predatory publications may be included in the resumés of scholars seeking employment or promotion and tenure.15

What are MEDLINE and PubMed policies for the inclusion of journals?

Both MEDLINE and PubMed are maintained by the National Library of Medicine, the world’s largest biomedical library, founded in 1836 within the National Institutes of Health.16 Among the library’s products, three — MEDLINE, PubMed and PubMed Central — play a prominent role in the access to and distribution of scientific knowledge.

These three databases overlap considerably, as shown in Figure 1. Users of the PubMed search engine query all three databases simultaneously as the default option. However, each database can be searched separately, because there are some important differences between them.

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Figure 1:

Venn diagram showing the overlap and unique features of PubMed and MEDLINE. References provided as of Sept. 30, 2017. Note: PMC = PubMed Central, refs. = references.

MEDLINE is the largest subset of PubMed; it started in print in the 1960s and contains more than 24 million references to journal articles in life sciences with a concentration on biomedicine, the largest fraction of which are included as PubMed references.17 A distinctive feature of a MEDLINE literature search is that the records are indexed with National Library of Medicine Medical Subject Headings (MeSH), the vocabulary thesaurus controlled by the National Library of Medicine that is used for indexing articles for PubMed.

PubMed was introduced in 1996 as an experimental database under the Entrez retrieval system; free full access to MEDLINE started from 1997. PubMed contains more than 28 million citations and abstracts from journals indexed in MEDLINE and, unlike MEDLINE, also life science journals and online books, which are free to access through the National Center for Biotechnology Information Bookshelf. PubMed also provides access to journals and manuscripts deposited in PubMed Central, additional relevant websites and links to the other molecular biology resources at the National Center for Biotechnology Information.

PubMed Central is an electronic archive of full-text journal articles that offers free access to its content. It contains more than 4 million articles, most of which have a corresponding entry in PubMed, and a small portion of which do not because they fall outside of PubMed’s scope (e.g., book reviews).18

MEDLINE and PubMed have different policies for journal selection, which means that just over 5600 journals are indexed in the former and about 30 000 are indexed in the latter (as of March 2018). The decision on whether to index a journal in MEDLINE is made by the Director of the National Library of Medicine based on quality and policy considerations that are set by the Board of Regents of the library. A Literature Selection Technical Review Committee is then responsible for reviewing journal titles and assessing the quality of their content. This committee comprehensively reviews applications through a multistep procedure.19 To cross-check a journal’s data, the procedure follows guidelines from the International Committee of Medical Journal Editors that were developed collaboratively by the World Association of Medical Editors, the Committee on Publication Ethics, the Directory of Open Access Journals and the Open Access Scholarly Publishers Association, and are based on principles of transparency that represent a minimum set of criteria to meet and maintain when seeking membership in any of the four organizations.20

The strict processes and criteria outlined above for a journal’s inclusion in MEDLINE are not mandatory for inclusion in PubMed and PubMed Central. Although open access journals and publishers indexed in MEDLINE are retrievable in the Directory of Open Access Journals and the Open Access Scholarly Publishers Association, a worrying number of those indexed by PubMed are not listed in either directory, because PubMed policies for journal selection are less strict. As a result, PubMed may well include journals that either did not apply for MEDLINE indexing, or did apply but did not satisfy minimum criteria for inclusion.

Other factors, such as the need to deposit research funded by the National Institutes of Health under the Public Access Policy, the broader scope and the wide range of available material in PubMed compared with MEDLINE, may contribute to the absence of many PubMed citations in the whitelists of the Directory of Open Access Journals and the Open Access Scholarly Publishers Association.

What are the potential loopholes?

The journal selection policy for PubMed Central comprises a pre-application — a requirement for an ISSN number, which is easy to obtain;21 a two-year history of publication; and a minimum of 25 peer-reviewed articles — followed by a six-step procedure (i.e., Submit Application, Initial Application Screening, Scientific Quality Review, Technical Evaluation, Pre-Production and Release to Live).22 This is a looser and apparently more flexible procedure than MEDLINE’s; it is supervised by the National Library of Medicine, which also provides a qualitative review. Although the preapplication phase does consider conformance with guidelines and best practices published by professional organizations, including Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals from the International Committee of Medical Journal Editors,23 Principles of Transparency and Best Practice in Scholarly Publishing20 and the Recommended Practices for the Presentation and Identification of E-Journals from the National Information Standards Organization,24 this process is not always uniform. Some journals indexed in PubMed Central are less than two years old and with fewer than 25 articles (often fewer than 10, even after counting the total number of articles issued on the journal’s website), which can be easily verified by searching the journal’s or publisher’s name in the National Library of Medicine’s catalog (www.ncbi.nlm.nih.gov/nlmcatalog/) to check the publication start year and the number of articles published in that journal.

The National Library of Medicine may consider an application from a publishing organization that has been publishing scholarly content for less than two years if there is evidence that the management and individuals responsible for editorial quality and operations have adequate experience in comparable positions at other organizations. That is, any journal or publisher candidate that did not apply for or meet criteria can be indexed in PubMed Central if they show that at least one credible published author is listed among its editorial board. However, it has been reported that predatory journals often use the identities of reputable researchers, who are unaware of being listed in the editorial board of these journals.25 This may explain the unauthorized use of academic names for editorial boards and the relentless number of daily invitations many researchers receive to join an editorial board of a never-heard-of journal.

In its qualitative review of candidate journals to be considered for inclusion in PubMed Central, the National Library of Medicine considers the 16 recommendations outlined in the guideline from the International Committee of Medical Journal Editors23; however, in the absence of any assessment from MEDLINE’s Literature Selection Technical Review Committee, the journal’s title and publisher’s name are not double-checked with the lists of these directories. Predatory journals often register journal names very similar to established legitimate journals and may not be recognized as fraudulent. As a result, open-access journals that do not qualify for inclusion may be indexed in PubMed Central and subsequently “leak” into the PubMed database.