Again, we shouldn’t be in the business of determining the number of authors but I can live with Dean Whitehead limits.

Chia-Lin - as your facts and stats suggest - the question of when are there too many authors is subjective and variable between disciplines. However, I think that many would agree that anything above 10 is questionable with the caveat that we are mainly referring to 'contained' primary research studies. By this, I mean that a longitudinal, multi-site, international study would potentially be an exception. Instead, let's take an 'average', localised clinical trial. The research team would 'typically' comprise the research leader CI (maybe two), a few PI's, a statistician, a few research assistants (probably collecting the data) and an overall consultant. My argument is that, after this, the study runs the risk of other authors being 'friends' or members of a wider research network that the lead researchers have worked with before or want to work with in the future. My question is that, after say 10 authors, what are the 11th, 12th 13th author etc doing?

I think the record in physics is more than 5000 authors 😊 https://www.nature.com/news/physics-paper-sets-record-with-more-than-5-000-authors-1.17567

I agree with Dean, its up to the topic.. it also should be mentioned that the article type also can determinate the max number of authors. In full research papers there is generally no upper limit. In research notes (less than 1000 words articles) or comment pieces usually the upper limit is 5 authors. In correspondence and short articles generally the peer reviewed journals request no more than 2 authors.

Your stats clearly point out that in my discipline (social sciences) should be up to four. Dr. Chang, 6 authors with unparalleled contributions is acceptable.

Dear Dean Whitehead:

Thank you for your insightful and detailed response.

The issue of a meaningful contribution to team research is an important one, which is why a number of publications in the sciences have been reported as: Author A, Author B et al., rather than Author A et al.

Dear Bence Mátyás:

Thank you for your helpful response, the breakdown in terms of article type, and the useful website.

There would seem to be a clear distinction as to an appropriate number of authors according to the type of article being considered.

Dear Temitayo O. Olaniyan:

Thank you for your helpful response.

I agree that the contribution of all authors is crucial and warranted.

Dear Frederick Clayton Berry:

Thank you for your helpful response and the APA Style Blog.

One could not possibly disagree with an academic who likes Snoopy and Woodstock.

Chia-Lin - anonymising authors i.e. Author 1, 2 or A,B is another debate perhaps - but one that I think is useful. Rather than 'how many authors' it becomes more an issue of author order/contribution. I know that some journals (and others contemplating) use alphabetical order. I suppose that the issue then becomes, say with my surname, if I had contributed most to the article - but was last, second-to-last on the author list - how would I feel about that. Universities, such as Flinders, are looking at different systems of scoring 'author order'. In the past, scoring was based on how high up the author order one was. Now - all authors score the same, regardless, of the author order - where those authors are in the same establishment.

I am impressed by the serious, detailed and considered responses to this important, challenging and vexing question.

Apart from an academic's personal assessment of their contribution to a research paper, institutions and research grant bodies frequently require a formal declaration regarding an author's percentage (%) contribution to a publication.

This must be problematic in the case of multiple authors (especially in 4 figures).

Dear Joshua O. Ighalo:

Thank you for your helpful response in respect of the unwritten rules across academic disciplines and the non-discrimination of co-authorship.

Dear Dean Whitehead:

Thank you for your considered response regarding the ordering of authorship and contributions to a research paper by each member of the collaborative research team.

Dear Michael John McAleer:

Thank you for your encouraging and thoughtful response regarding the requirements for a formal declaration of contributions by each member of a collaborative research team.

That's true on percentage Michael. Also - many journals now ask for author initials aligned to various parts of the research/manuscript process - usually placed at the end of the accepted article. What we can often see is that the last author (? consultant) is usually only credited against the manuscript contribution - and not the research design process.

Dean, you are perfectly correct in mentioning that many journals, especially those with Open Access publishers, report the specific contributions to the journal publication.

This makes it clear how and which authors contributed to the journal publication.

In a number of journal publications in medical research, among others, the last-named author may be seen as "supporting" the research program as the major recipient of a large research grant.

As long as the team members in a collaborative research program, and the research evaluation bodies, know how to interpret intellectual, technical, experimental, administrative and financial support contributions, the order and number of authors need not be of great concern.

Dear Dean Whitehead:

Thank you for adding another dimension to the discussion regarding explicit statements of contributions to collaborative team research.

Dear Michael John McAleer:

Thank you for contributing additional interesting and helpful ideas regarding author contributions to collaborative research.

Agreed Michael. Our agreement, however, may have a bit of a 'Westernised lens' spin on it. Any research that I am involved in IP, grant order, author order etc are all pre-negotiated and there is no deviation from it - unless obvious circumstances change i.e. members of the team leave etc (although any contribution to date is acknowledged). The senior members of the team are experienced, committed to mentoring and know how to get good outcomes from a team. To me - the senior members of the team cluster into two categories - depending on a whole range of factors. The first category is those, as you state, that are not overly concerned on 'taking the back seat' even when they are front-seat drivers. Then there are those who are more 'controlling'. As an editor and reviewer, what I am noticing more, of late and from certain geographies etc, is that author disputes are occurring more. More journals, including a few I involved with, are addressing this. After first review, for instance, the instructions may state something along the lines of avoiding any changes in authors or author order as it 'may' result in protracted delay. What is happening is that 'teams' are fine (or appear to be) with things until it starts to look 'more real' that a publication/s will occur. Then authors start disputing to the journal editors and they don't want nor need that complication.

This question is turning out to reveal some very interesting 'spins' and directions if you ask me!!

To Dean:

Many thanks for adding a carefully considered and detailed response, with which I am in total agreement.

Chia-Lin Chang seems to have raised an issue that can turn in many directions.

Dear Dean Whitehead and Michael John McAleer:

I have benefited greatly from your interesting intellectual interaction regarding the recognition of the rights and responsibilities of joint authors in team collaborative research.

Wonderful response

I agree with you.

Dear Pritam Kumar Panda:

Thank you for your enlightening comments regarding research in clinical medicine and physics, and interactions with the corresponding author.

Dear Chialin

I prefer 3 or 4 as we have to work in a team.

thanks

Dear Duc:

Thank you for your helpful response regarding collaborative team research.

I can understand how some Big Science projects might involve research and engineering teams from many disciplines plus a lot of relevant and necessary administrative oversight, all of which are sine qua non for getting the results that are eventually published in a paper: ergo many 1000s for some physics projects; e.g. an apparent record of 5,154 in the case of a Hadron Collider research paper:

https://www.nature.com/news/physics-paper-sets-record-with-more-than-5-000-authors-1.17567

Perhaps in such cases a link should just be provided rather than a list of all the authors in the paper itself.

What I can't understand is some papers coming from non-Big Science projects (e.g. in psychology) with a couple of hundred coauthors. Are people being awarded coauthorship for sharpening pencils, taking out the trash, or getting coffee? (Film credits often seem like that nowadays.) I was once offered credit as coauthor on a social science paper for simply sending out a questionnaire I was given and returning the filled-out forms I received.

Dear Karl:

Thank you very much for your detailed and helpful response.

It would be virtually impossible for any paper in most disciplines in the sciences and social sciences to come close to having thousands of co-authors.

The names of the authors and their affiliations would take up much more space than the academic content of the paper itself.

Inclusion of names might be related in some cases to potential litigation in the event that a justifiably (or not) aggrieved academic seeks redress for having been omitted as a co-author.

Not a direct contribution to the discussion, just a humerus take on the issue.

Dear Sven:

Thank you for the humorous and philosophical take on the issue.

What great answer from Pfeifer.

Dear Chia, in one paper in Indonesia, there are two to four authors, this is for research papers, if the paper is conceptual, the author is a maximum of two people.

Dear Saif Abdul Hussein Moamin:

I agree with your assessment.

Dear I Putu - Artaya:

Many thanks for providing an Indonesian perspective on research and conceptual academic papers.

The general consensus seems to be as many authors as are required to complete the paper, within reason.

Dear Michael John McAleer:

Thank you for your thoughtful Answer.

You may well be right.

While the journal policy say authers so it opened number. I already read a paper with seven authers.

Dear Saif Abdul Hussein Moamin :

Thank you for the helpful Answer about published papers with several authors.

You welcome my dear.

More than 4

Dear Mohammed Almayyahi :

Thank you for your helpful and numerical answer relating to the number of authors on a single research paper.

"An important" addendum (the upper bound) to the previous answer by Mohammed Almayyahi (15 hours ago):

“and less than infinity.”

Many with no boundary, but each author has reason to be included in the article

Dear Romeo:

Thank you for setting the countably finite boundary for the number of authors on a single paper.

Dear Yosef Tadesse :

Thank you for your boundless answer and the emphasis on valid reasons for including authors on papers.

To All:

These are very helpful and informative discussions, for which great appreciation should be offered.

If this is intended as a rhetorical question, for which the Answer could be any finite number, I would Answer the Question with another Question:

https://www.researchgate.net/post/How_long_is_a_piece_of_string

A sincere and appreciative acknowledgement for the very helpful and thoughtful Answers.

Another issue related to attempts to increase the RG score, which might not work for the number of authors, is repeatedly using one-word Answers, such as "Following", for which an interesting one-word alternative response is "Accepting".

One makes as much or as little sense as the other.

You have updated this very helpful suggestion with an interesting Question:

https://www.researchgate.net/post/Which_is_the_most_popular_one-word_Answer_Yes_Following_Agreed_or_Accepting

Dear Michael John McAleer:

Thank you for updating the Question with another Question that helps to clarify responses using one -word Answers.

3 is good.

Dear Emad Kamil Hussein :

Thank you for your helpful and informative numerical Answer to the Quesiton.

An interesting related thread is the following Question, which has 6,432 Answers:

https://www.researchgate.net/post/What_do_you_think_about_single_author_paper

Dear Michael John McAleer:

Thank you for the interesting and informative related Question.

It is interesting to see 6,930 Answers to the following related Question:

https://www.researchgate.net/post/What_do_you_think_about_single_author_paper

Any finite number.

Dear Awanish Kumar:

Thank you for your helpful Answer.

Following..

Dear Abdul Kuddus :

Thank you for your interest in the Answers relating to this Question.

It is open number ... as long as they all share doing or writing the same research together ...

So Any number of authors you can imagine could be there on the research .

Dear Rizk Elazhary :

Thank you for your helpful Answer regarding related research topics.

A reader of a paper is not interested in the number of authors but its content. Then, there is this public acceptance of an issue when they see that many persons have looked into. The same applies to a paper. Even when a commercial is shown about a product, what one often sees is bunch of people showing they acceptance of the product. Medical journal papers have tended to have authors more a dozen. This is health matters, therefore non-health research can as well as have less than a dozen authors as long as it is okay with the authors

Dear Chuck:

Thank you for your detailed, helpful and informative Answer.

I absolutely agree with Dean.

By my opinion interdisciplinary and multidisciplinary work may demand more co-authors.

Dear Jelena B Popović-Djordjević :

Thank you for your helpful Answer regarding interdisciplinary and multidisciplinary research.

Dear Vladimir Mirkovic :

Thank you for your insightful answer regarding the number of authors on research papers in Economics.

To Vladimir Mirkovic:

Sorry, I do not agree with your statement because it is incorrect! Further, making such rigid statement leaves a reader with a limited view of economics. I have asked my son to go search my garage because you comments doesn't make sense!

Dear Chuck:

Thank you for your helpful and informative Answer regarding what constitutes an appropriate number of authors on a research paper in Economics.

To Vladimir Mirkovic:

Here are some examples from journals that A++

The Review of Economics and Statistics (RESTAT) August 1998 vol LXXX with 10 authors

RESTAT August 1999(2) Vol. LXXXI with 4 authors

Journal of Business &Economic Statistics (JBES) April 2001 Vol 19(2) with 4 authors on pp208

JBES April 1998 Vol 16(2) with 5 authors , see p 127.

The problem I have with your statement is that you create an unnecessary dissipitation of energy to clean what you said. Please do not make statments that are without substantial. I support what Michael J. McAleer wrote above:

"As long as the team members in a collaborative research program, and the research evaluation bodies, know how to interpret intellectual, technical, experimental, administrative and financial support contributions, the order and number of authors need not be of great concern."

Surely a relevant question. Congratulations! In a collective sense, it looks that the true author is the human species with every inherent fails and virtues. In a strict sense, it seems that authors should be just all those that in a given period contributed effectively for the research that is presented in the publication. Interesting from a contemporary perspective in the current society of information (where everything occurs and is forgotten very fast) is if the name and number of authors may become much more relevant that the scientific content of the research.

As many authors as contributed.

Dear António Manuel Abreu Freire Diogo :.

Thank you for an instructive Answer from a distinguished academic at a distinguished institution.

Dear Volodymyr Brazhenko :

Thank you for a clear and helpful Answer.

Dear Chuck:

Thank you, as always, for your prescient Answer that is supported by facts.

Dear distinguished academic, Chia-Lin Chang

Thanks for the fact that you gave sincere and instructive compliments that I much appreciated.

Dear António Manuel Abreu Freire Diogo :

It is my pleasure.

Just stating fact.

Many thanks for the interesting website.

I am returning one I am sure you have seen:

https://theculturetrip.com/europe/italy/articles/the-12-oldest-universities-in-the-world/

I prefer to the maximum of 5. However, 3 appears to be optimal in particular all authors come from the same affliliation

Dear Duc Vo :

Thank you for your helpful and informative Answer regarding the number of co-authors from the same and different affiliations.

I prefer 3 authers as contributed

Dear Shurooq Alshaibani :

Thank you for your interesting Answer.

Again, we shouldn’t be in the business of determining the number of authors but I can live with Dean Whitehead limits.

Dear Chuck:

Thank you for your insightful Answer, as always.

"Over the past five years, the number of papers in the Nature Index with more than a thousand authors has surged from zero to a hundred."

https://www.natureindex.com/news-blog/paper-authorship-goes-hyper

Please see a related old interesting RG question “Who should be among co-authors of the scientific paper? TOPIC CLOSED (available at https://www.researchgate.net/post/Who_should_be_among_co-authors_of_the_scientific_paper_TOPIC_CLOSED, asked October 3, 2013).

Dear Michael John McAleer:

Thank you for an interesting and useful website.

Dear Romeo:

Thank you for a related RG thread which seems to be ongoing rather than Closed.

This interesting Question is ineffable, far more so than:

https://www.researchgate.net/post/How_Many_Angels_Can_Dance_on_the_Head_of_a_Pin

It limitless. Depends on the number of people on the project that brought about the article.

Five and above many

Good two or three

Four upper limit

Five and above there are, of course, people who have been added who have not submitted anything

Dear Michael John McAleer:

Thank you for an ineffable Answer and useful website.

Dear Maurice Ekpenyong :

Thank you for a discerning and helpful Answer.

Dear Taher Alkhalaf :

Thank you for an interesting numerical Answer.

It depends on the study nature. In social Sciences, usually authors are plus minus 5. Some people suggest that fewer authors in an article has more value. Again, it depends on the situation and work involved.

Abbas J. I agree with you. There are not many authors in social sciences but the number of authors in experimental papers may be quite many too.

Dear Abbas J. :

Thank you for your detailed and helpful Answer.

I saw a paper published with around 10 authors (secondary data paper) last year and till date it has more than 1000 citations.

Dear Hom Nath Chalise :

Thank you for your interesting and supportive Answer.