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Feature Christmas 2017: Language and Literacy

Non-existent authors

BMJ 2017; 359 doi: (Published 13 December 2017) Cite this as: BMJ 2017;359:j5706
  1. Jeffrey K Aronson, clinical pharmacologist
  1. Centre for Evidence Based Medicine, Nuffield Department of Primary Care Health Sciences, Oxford, UK
  1. jeffrey.aronson{at}

Databases of the scientific literature have accredited some unusual authors, finds Jeffrey Aronson

Authorship of bioscientific papers is a serious business. Most journals have policies that encourage transparency, making it clear who did what, but some authors take it less seriously than editors might like, and indexers don’t always get it right.

Searching for common abbreviations (table 1) in PubMed (1809–2017), Embase (1974–2017), Ovid Medline (1946–2017), Philosopher’s Index (1966–2016), and PsychINFO (1806–2017), I found three types of non-existent authors: apparent authors (such as Et Al and Anon), which conceal the identities of real contributors, depriving them of recognition; apparent authors whose “names” are postnominals, such as “Phil D”; and authors whose initials have been used as surnames and surnames as initials.

Table 1

Explanations of the abbreviations used in the searches

View this table:

Here I explore two of these categories in more detail, and discuss other forms of authorship.

Et al and anon

Searching for “et al[au]” yielded 51 474 hits in PubMed (fig 1), 54 199 in Medline, 9896 in PsycINFO, 1453 in Philosopher’s Index, and 264 in Embase.

Fig 1
Fig 1

Numbers of publications with “et al” or “Et Al” as senior author year by year (source PubMed); the changes in frequency to some extent reflect changes in the rules regarding substitutions of authors’ names with “et al”, as shown in the explanatory boxes. *From 1973 “et al” was used in a few cases for more than one author, with no obvious logic; † three journals used et al for more than 1, 3, or 4 authors totalling 11 papers in 2002, 23 in 2008, and four in 2009

Et Al seems to be a highly prolific author whose identity is shrouded in mystery. He or she has authored nearly 60 000 papers and is always the last person mentioned, suggesting a degree of seniority. I imagine this author as someone called Etiocles Alexippus or his sister Ethoda, perhaps both. Their most prolific period was from 1983 to 1999, with nearly 41 000 papers, in collaboration with authors from institutions all over the world. Perhaps the earlier output, during 1945 to 1950 (over 10 000 papers) was attributable to the work of Etearchus Alexippus, their father. Other prolific authors, such as Smith J (nearly 24 000 hits) and Ma Y (over 14 000), come nowhere near this massive output, and although Kim J (over 73 000 hits), Lee S (over 74 000), and Zhang Y (over 87 000) are serious rivals, I suspect that those names hide multiple identities in consortiums aiming for high h indexes.

There is no profile for Et Al in Google Scholar, but 41 papers, randomly sampled, have garnered 3712 citations (range 0-1455; median 21). I therefore estimate that Et Al’s papers have been cited about five million times. Thus, the h index (0.54√N, where N is the total number of citations1), is about 1200; in other words, 1200 of Et Al’s papers have each garnered at least 1200 citations.

Et Al should not be confused with the common epicene abbreviation for Latin versions of “and others” (table 1). This abbreviation was first recorded in an English text in the Handbook of Abbreviations by Samuel Fallows, published anonymously in 1883.

A search for authors with the surname “Al” yielded 364 examples, a few of which were parts of longer names, such as Abdul-Al; disappointingly, none had the initials ET.

Searching for “anon[au]” yielded 230 hits, but 218 of those were by authors whose surnames really are Anon or Añón (perhaps a shortened form of Añónuevo). I retrieved seven of the other 12 papers; all were signed “Anon” or “Name and address supplied.” Typically, when names are not included in a paper, PubMed enters “[No authors listed]”. However, in two cases multiple items with named authors were attributed to “Authors V.”


Postnominals appear as authors in many papers. An author called “Biol MI” has two entries in PubMed. There are many examples of authors called Md (fig 2) and one Dm; one paper boasts five authors called Md and one Md Phd. In a few cases “Md” is an abbreviation of Mohammed or a variant spelling.

Fig 2
Fig 2

Example of two apparent authors listed in PubMed as Md. The journal gives their names as Piysuh Somani MD and Udayakumar Navaneethan MD

PubMed also includes papers by authors called Chir M, B, or MB (n=21), Tech M (11), Mrcp (2) and Frcp (1), Mb (2) and Mbbs (4), Frcs (2), Fracp (12), and one by Mbbs & Fracp, Two papers name authors called Mbchb, one with a coauthor called Phd.

Phd is a coauthor in 13 papers, and his Oxonian cousin Phil D in 27 (90 cases in EMBASE).

In a few cases postnominals were erroneously listed as authors in the journals themselves.


I searched several databases but did not combine the results and deduplicate them. A comparison of differences between databases would be interesting. For example, the data on “Phil D” (23 hits in PubMed and 90 in EMBASE) emphasise possible differences.

I will have missed instances of non-existent authors whose names were misprinted. For example, had I not mistyped “et al” as “er al” when searching Ovid Medline, I would have missed three misprinted instances of papers by Et Al. Such instances are probably uncommon. I will also have missed instances in which authors’ surnames are given as initials and initials as surnames (fig 3).

Fig 3
Fig 3

Example of authors’ forenames and surnames being switched in PubMed

Other forms of authorship

Other forms of authorship, which can distort the literature, deserve mention here.

  • Gift or honorary authorship—Authorship is sometimes given to people who do not deserve it, such as heads of department. The estimated prevalence of gift authorship in six peer reviewed medical journals was 11–25%.2 The guidelines of the International Committee of Medical Journal Editors specify criteria for authorship and state that acknowledgment of non-author contributors is sufficient.3

  • Hidden (ghost) authors—A ghost author is someone who makes contributions that merit authorship or contributes to writing the article but is not listed as an author. This fails to give appropriate credit and may be an abuse if the ghost author is, for example, a member of a company that manufactures a medication and has an undeclared interest in the study. The estimated prevalence of ghost authorship in six peer reviewed medical journals was 7–16%.2

  • Fake authorship—Occasionally an author includes the name of a non-existent author. One Spanish author included an author who could not be traced in papers that were later retracted.4 In one unusual case, a scientist’s work was published by five others using fake names.5

  • Pseudonymous authorship—Some authors have legitimately used pseudonyms. They include William Gossett, who described “Student’s” t distribution,6 the consortium of mathematicians called Nicolas Bourbaki,7 and other mathematicians.8 Some have wanted to use the screen handles under which they did computerised research, but editors have insisted on their real names for the sake of accountability.9 The increasing use of pseudonyms in academic blogs may be a cause for concern.10 Fake authorship and pseudonymity should be distinguished from anonymity (see above) and from spoof articles published under authors’ correct names,11 or even pseudonymously,12 when such articles are used to test the acceptance procedures of journals.13 ORCID digital identifiers14 will probably make it more difficult to indulge in fake and pseudonymous authorship.

  • Non-human authors—Artificial intelligence programs and animals are two sources of non-human authors. Box 1 lists two notable examples of some who certainly seemed to be authors, but not authors as we know them.

Box 1

Dogs as coauthors

In the 2000 Christmas issue of The BMJ, a paper appeared in which Chen and colleagues described three examples of a novel alarm system for hypoglycaemia in people with diabetes.15 The system consisted of stereotyped behaviour by the patients’ dogs. In one case, for example, the dog jumped up, ran out of the room, and hid under a chair, re-emerging only when the patient had taken some carbohydrate. Three of the authors N, S, and C Williams, respectively described as “junior research assistant”, “intermediate research assistant”, and “senior research assistant”, were in fact the dogs, Natt, Susie, and Candy. As proof of their agreement to be coauthors, their pawprints were published in the paper. It is not clear by what right they assumed the surname Williams.

● In 1978 Polly Matzinger and a coauthor reported experiments showing that fully allogeneic chimeras made by repopulating irradiated BALB/c(H-2d) mice with BALB.B(H-2b) bone marrow were able to respond to minor histocompatibility (H)2 antigens, and that the killer T cells that were themselves H-2b could recognise minor H antigens on either H-2b or H-2d targets.16 Throughout the paper Matzinger used the pronoun “we”, but it later transpired that her coauthor was her dog, recruited so that she could avoid both the passive mood and the pronoun “I”. Probably the editors of the journal were not familiar with the works of J R R Tolkien, or they would have recognised the elvish provenance of the coauthor’s name, “Galadriel Mirkwood.”



A prosaic interpretation of these observations is that indexers do not always realise that a postnominal such as MD, MBChB, or DPhil is not actually an author’s name and that some of them have misinterpreted the meaning of the Latin abbreviation “et al.” In some cases errors of this sort cluster in individual journals, perhaps because of idiosyncratic indexing by one person.

The databases I searched are unlikely to take the trouble to correct existing errors, which also have the benefit of being amusing, unless authors ask them to. However, these errors have deprived some contributors of the credit of authorship and ought to be corrected. The abbreviation “et al” should not be used in databases, nor, I suggest, in citation lists in journals, including this one—electronic publication relieves journals of the need to save space.


I thank Kamal Mahtani, Tim Muntinga, Jack O’Sullivan, and The BMJ reviewers for helpful comments.


  • Competing interests: I have read and understood BMJ policy on declaration of interests and declare that although I found 31 papers including namesakes (eg, Aronson KJ) as coauthors of Et Al, I have never been one myself, although there is one instance of “et Al JK”, because the journal, Gene Therapy, published a corrigendum under the authorship of J Kayaga et al. Most of my postnominals have appeared as authors of scientific papers, and I admit to being jealous of Et Al’s citation rate and h index.

  • Provenance and peer review: Not commissioned; externally peer reviewed


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