Brands set and fulfill customer expectations. Dunkin’ Donuts coffee or Starbucks? There’s not much practical difference, but there is a difference in expectations.

In a well-defined brand family, you know which end is up — with Toyota, we all know the Avalon is above the Camry is above the Corolla is above the Yaris. Even less obvious brand relationships, when well-managed, convey this implicit hierarchy. Marriott does an excellent job of conveying rank within a set of brands that aren’t obviously related, with Ritz-Carlton and Bulgari at the top, down through Marriott to Courtyard to Fairfield Inn.

It’s no secret there’s widespread confusion about the brands the National Library of Medicine (NLM) is using to describe its bibliographinc databases and indices of citations to the biomedical sciences — PubMed, MEDLINE, and PubMed Central.

Make no mistake — these are brands, complete with trademark registrations and protections, each intended to designate a specific function or service. And there is a hierarchy the NLM seems to want to establish, with MEDLINE atop the brand pile, at least conceptually, if not practically. In statements, entries are “elevated” to MEDLINE from PubMed, for instance. It is their best-managed brand, even if it’s not their best-promoted brand.

Unfortunately, these strong brands aren’t being managed very well, leading to confusion in the marketplace. Editors, librarians, publishers, and authors fall into the layers of confusion from time to time.

The brand confusion is even baked into the Web. For instance, if you use Google to search the phrase “indexed in PubMed,” the first link you get is to a page entitled, “List of Journals Indexed for MEDLINE,” which talks about how the publication “List of Journal Indexed for MEDLINE” ceased publication after 2008. The second link isn’t much better — a link to an FAQ about journal selection for MEDLINE inclusion. In here, at question 17, you finally get a link explaining the differences between PubMed, MEDLINE, and PubMed Central. However, on some questions, the entity is still listed as “MEDLINE/PubMed,” underscoring the notion that the two are equivalent.

The confusion is also baked into the NLM’s site architectures, with the menu for “PubMed/MEDLINE” on this page resolving to a page that is labeled “PubMed” and has a PubMed URL (http://www.ncbi.nlm.nih.gov/pubmed/).

The confusion goes deeper in casual usage, with editors, authors, and NLM employees themselves using “PubMed” as a shorthand for “PubMed Central.”

The conflation occurred in two stages. Initially, PubMed was created in 1996, as a free online version of MEDLINE. This linked PubMed and MEDLINE, but because PubMed was linked to the Internet, it became the de facto public name for MEDLINE. Then, when journals included in PubMed Central were automatically listed in PubMed, this ended the era of equivalency between MEDLINE and PubMed. The PubMed brand was being extended beyond MEDLINE, but remained conflated with it.

Since then, the PubMed brand has been extended in two ways — as PubMed Central (which seems like a sub-brand of PubMed), and as PubMed Central’s registration service. This expansion of duties for the PubMed brand has led to confusion in the marketplace, and even confusion about whether records in PubMed are “indexed” or “included.”

As you likely know, I filed a Freedom of Information Act request late last year, as part of an investigation into how PubMed Central colluded with eLife to give eLife unprecedented launch advantages, up to and including providing them with immediate PubMed listing and robust online publication support. As part of this request, other emails tangentially related also surfaced, including one discussing whether we should call being listed in PubMed “indexed.”

On November 13, 2012, David Gillikin, Chief of Bibliographic Services for the NLM, writes in an email to other NLM staff, referring to a post I had published the day prior:

This email reminded me of the conversations going on at the periphery of these discussions of PubMed Central — whether or not there’s confusion about the NLM’s brands. And it introduced a new item — whether some brands represent indexing or simply deposit in a database. From a bibliographer’s standpoint, this is a technical but important distinction. From an editor’s or author’s point of view, it’s also important to understand — the assumption is that being indexed in PubMed signifies a major endorsement of a journal, after serious review by experts at the NLM. That’s the brand promise as understood on the market.

Unfortunately, it’s the brand promise of MEDLINE, not PubMed. And this is the root of much confusion.

There are other clues that this distinction is recognized internally at the NLM. In a different set of FAQs, the NLM refers to PubMed in this manner:

PubMed is a database of citations and abstracts for millions of articles from thousands of journals.

It’s not an index in this setting, but a database.

I asked Gillikin via email yesterday about this, and he provided a very helpful response:

Gillikin is observing here that it’s OK for general users to call inclusion in the PubMed database “indexing,” but this contrasts with the prior email correcting my usage. I think he’s saying that the public may call it “indexing,” but people who should know better should, well, know better. He may be experiencing the same conflation of brands, and brand promises, we’ve been talking about. They are difficult to untangle at this point.

If your audience is confused about your brands, it’s not their fault. It’s like Buick blaming me because I don’t understand their brand hierarchy involving the Regal, the LaCrosse, and the Verano. (Many auto brands solve this problem by taking the direct route in their branding hierarchy, using progressive numerical or alphabetical schemes — BMW 300, 500, 700; Audi 4, 6, 7; Mercedes C, E, G, S; Jaguar XF, XJ, XK; Infiniti EX, FX, G.)

There is a practical sticking point within the brand conflation at the NLM, one that publishers behind the 90% of the papers in PubMed that are indexed in MEDLINE probably appreciate — it takes a lot of time, effort, and patience to be indexed in MEDLINE. Being indexed in MEDLINE is a non-trivial accomplishment, much harder than being included in PubMed via inclusion in PubMed Central. To have this work and effort equated with PubMed Central records that come in via different criteria doesn’t seem right. The processes are not equivalent, and the resulting records are not, either. By allowing the PubMed brand to signal equivalency for journals not indexed in MEDLINE, the NLM is drawing value from MEDLINE journals and sharing it without permission with non-MEDLINE journals. Because PubMed and MEDLINE are conflated brands now, their value is intermingled.

The pathway into PubMed for OA content via PubMed Central is also becoming less disciplined, it appears. In addition to how eLife was expedited behind the scenes and apparently without following any process, PubMed now includes non-journals that don’t even know when their papers are ready for PubMed inclusion because their peer-review process is so poorly managed.

But the phrase “indexed in PubMed” has nearly talismanic powers, which OA publishers whose content is only included in PubMed wield proudly. I don’t blame them. The brand confusion is widespread, it’s not their fault, and it feels natural in our community to say “indexed in PubMed” no matter how you were included.

Once you understand the branding problems and conflated promises extant in the PubMed brand, it becomes easier to see why there’s a problem. Examples are plentiful, as in this statement from F1000 Research, a non-journal now “included” in PubMed, shows:

Once an article has received two ‘Approved’ statuses from the referees, or one ‘Approved’ status and two ‘Approved with Reservations’ statuses, the article will be indexed (in PubMed, PubMed Central, Scopus, Embase and others)

If the difference between the MEDLINE brand and the PubMed Central brand were clearer, the better wording would be “included in PubMed, PubMed Central, Scopus, Embase, and others.”

The confusion continues, with SPARC’s page about “Getting Your Journal Indexed” perpetuating the general misunderstanding that PubMed is an index:

Though each discipline may have indexing and abstracting services specific to the field, the most well-known, well-regarded services include:

• AGRICOLA (AGRICultural OnLine Access)
• Biosis Previews®
• Chemical Abstracts
• ISI® Web of Science
• PubMed

Do they mean MEDLINE? Again, the NLM brands are not well-sorted, leading to substitutions that add value to the PubMed brand while decreasing the value of the MEDLINE brand.

There are different forms of confusion about PubMed Central, PubMed, and indexing, as this page from Frontiers shows:

In the next coming months all the articles published in the journal will be indexed with the Full Text in PMC and citation in PubMed.

The confusion has even lead to correction notices, as in this example from Open Medicine, a Canadian OA journal:

This corrected editorial replaces the version published on 5 January 2010, which stated that Open Medicine is indexed in MEDLINE, when in fact it is indexed in PubMed (of which MEDLINE is a subset). Open Medicine currently has an application under review for indexing in MEDLINE.

The Open Medicine team is pleased to announce our recent acceptance for indexing in PubMed—an official stamp of approval from the US National Library of Medicine (NLM) for the scientific and technical quality of articles published in our journal.

This correction still perpetuates two errors — PubMed is not “an official stamp of approval” from the NLM in this case, for anything other than inclusion in PubMed Central, which has different and “flexible” standards; and MEDLINE is not a “subset” of PubMed, as in an embedded brand, but a higher level of approval, a superior brand. (Open Medicine has subsequently been approved for the MEDLINE index, which is what their initial brand sense had correctly identified as the one to really brag about.)

Interestingly, eLife has been a bit more savvy about this, at least if this interview from late 2012 with Mendeley is any indication:

Q: Will eLife be indexed by Pubmed? Google Scholar?  How will you ensure an author that your articles will be easily discoverable by readers?

A: The eLife journal will be hosted by Highwire, who have a very good working relationship with Google Scholar. As you know by now, our content is also listed on PMC, Europe PMC and PubMed.

Notice they don’t quite correct the interviewer, but also don’t compound his or her error about indexing.

These brands — PubMed and MEDLINE, in particular — are important, as are the perceptions they engender. For instance, I’ve encountered authors who want to know specifically if a new journal is “indexed in PubMed.” If it’s not yet, they might withdraw their paper. Maybe they only want the journal to be “included” in PubMed, but I’m pretty sure they want certification beyond mere presence in a search engine. Their real question is about being indexed in MEDLINE. But they don’t understand the differences, and therefore transfer the brand promise of MEDLINE to PubMed. In so doing, and considering the backdoor into PubMed, they are inadvertently giving PubMed Central extra authority based on transference of authority from MEDLINE through PubMed conflation.

Until these confusing brands and approval pathways are rationalized, we’d all do ourselves — and the NLM — a favor by being clear on the distinctions between being included in PubMed and indexed in MEDLINE. The NLM brand has power. The MEDLINE brand has power. The PubMed brand has power, some appropriated from the MEDLINE brand, some put at risk by PubMed Central.

Ultimately, the MEDLINE brand, and its sound processes, is the bedrock of the other brands’ power. But the NLM is hiding its light under a bushel, as the saying goes, for the sake of promoting weaker brands that draw down the equity of the MEDLINE brand. I believe they should lead with their most well-defined brand — MEDLINE — and sort the other two out from there.

Recent behavior aside, the NLM owes it to itself and its users to sort out its brands before they become even more confused, compromised, and bewildering.

(P.S. More confusion? Why does the NLM have both “Medline Plus” and “PubMed Health” as their consumer brands, despite the sites having virtually identical content?)