Indexes, ISSNs and how to judge a journal

Anyone can put up a website and call it a journal. For readers, that raises a practical question: what do the identifiers, index listings and badges on a journal's pages actually tell you, and what do they not? This page explains the common ones and the checklists researchers use to judge a publisher. It is general guidance and is not about any particular journal.

What an ISSN is

The ISSN International Centre explains on its page What is an ISSN? that an ISSN, or International Standard Serial Number, is an 8-digit code used to identify newspapers, journals, magazines and periodicals of all kinds, in print or electronic form. It takes the form of the letters ISSN followed by two groups of four digits separated by a hyphen, and the last digit is a check digit calculated from the other seven, which may be an X. The code is associated with the title of the publication, and if a publication changes significantly, a new ISSN must be assigned. The page adds that in many countries an ISSN is mandatory for publications subject to legal deposit.

What an ISSN is not

The same page is equally clear about the limits. It describes the ISSN as a code without any intrinsic meaning: it does not include any information about the origin or contents of the publication, and it does not guarantee the quality or validity of the contents. An ISSN tells you that a serial has been registered and gives you a reliable way to refer to it. It says nothing about peer review, editorial standards or reputation. A journal that displays its ISSN prominently, as if it were a mark of quality, is advertising a filing number.

What DOAJ does

The Directory of Open Access Journals describes itself on its About page as a unique and extensive index of diverse open access journals from around the world, and states that its mission is to increase the visibility, accessibility, reputation, usage and impact of quality, peer-reviewed, open access scholarly journals. It also says that DOAJ's criteria have become a gold standard for open access publishing. Unlike an ISSN, which any serial can obtain, a DOAJ listing reflects an application assessed against published criteria. Wikipedia's article on predatory publishing names the directory as one of the whitelists used to reduce the influence of deceptive publishers.

What being in PubMed means

PubMed's About page explains that it contains citations and abstracts of biomedical literature drawn from several sources. The largest component, MEDLINE, consists primarily of citations from journals selected for MEDLINE. Other citations come from PubMed Central, whose journals are reviewed and selected for inclusion, but which also holds individual articles deposited to comply with funder policies, and from books on Bookshelf. So the presence of a single article in PubMed does not mean its journal was selected for MEDLINE: an article can appear because its authors deposited it under a funding requirement. What a PubMed record confirms is that the article exists and has been catalogued, not that its journal meets any particular standard.

Predatory publishing

Wikipedia's article on predatory publishing, also called deceptive publishing, defines it as the use of exploitative and fraudulent publishing models by journals and publishers that put financial or reputational gain ahead of scholarship. It is characterised by misleading information about editorial practices, a departure from standard peer review, a lack of transparency and aggressive solicitation of authors. The article notes that the phenomenon of open-access predatory publishers was first noticed by Jeffrey Beall around 2012, that criticisms of the label itself have been raised, and that identifying such journals remains difficult because it is a spectrum rather than a simple yes-or-no category.

Among the complaints the article lists are: accepting articles quickly with little or no review; telling authors about fees only after acceptance; accepting papers outside the journal's declared scope; aggressively recruiting authors and editors; listing academics as editors without their permission; mimicking the name or style of established journals; making false claims about location; using ISSNs improperly; citing fake metrics; and boasting of being indexed by academic social networks or of carrying standard identifiers such as ISSNs and DOIs as if these were signs of prestige.

That last point connects directly to the sections above. Identifiers and listings each mean something specific, and the tell-tale sign of a deceptive publisher is often that it presents them as meaning something more.

Checklists, and their limits

Many organisations have published checklists to help authors avoid deceptive journals. One widely known example is Think. Check. Submit., which describes itself on its site as an international, cross-sector initiative that aims to educate researchers, promote integrity and build trust in credible research and publications. It offers checklists for journals and for books and chapters, to help researchers assess whether a journal or publisher is a suitable venue for their work.

A 2020 systematic review in BMC Medicine by Cukier and colleagues looked at such checklists as a group. According to its abstract, of 1528 records screened, 93 met the inclusion criteria; the checklists included a mean of 11 items, and only three met the authors' criteria for being evidence-based. The authors concluded that there is a plethora of published checklists that may overwhelm authors, that their continued development may be confusing and of limited benefit, and that the similarity between them could lead to one evidence-based tool serving authors in all disciplines.

Using this as a reader

For readers rather than authors, the lesson is to look past the badges. Ask whether the journal's scope matches the paper, whether its review process is described, whether its listings can be confirmed at the listing body's own site rather than only on the journal's pages, and whether the paper itself stands up to the kind of reading described elsewhere in this guide. No single identifier settles the question; together, careful checks usually do.