Academic paper typically has more than one author, because usually more than one person contributes to the works published. Being a co-author in another person’s paper contributes to the number of publications listed in your GoogleScholar, Researchgate, SCOPUS Author ID, and other academic profiles. And as mentioned in another post, having publications is important in advancing your academic career. On top of the reputational and CV benefits, becoming involved in other people’s research works helps to widen your field of expertise and gives new perspectives to your own works. In fact, I often gain new ideas for my own research after discussion with my colleagues about their work.

Becoming a Co-Author

To become a co-author, you need to add value to other people’s research. Go around and talk to your colleagues, find out more about their works and find ways where you can collaborate and contribute to each other’s works. Your software/tool/method may be usable by your colleagues in doing their work. If you are already doing this on a regular basis because your research group members do projects together or you have regular group meetings, then that’s great. If you are usually doing research on your own, then all the more reason to talk to people around you! Even if you realise that there is no avenue for collaboration just yet, just having the discussion and having other people’s inputs on your research can be extremely beneficial. If you are still unsure about what topics to pursue (next), such discussion can also help you to think of ideas. But if you do discover that there is so much that you can contribute to other people’s research, don’t spread yourself too thinly. While helping others and co-authoring multiple research papers at the same time are great, you still need to have time to do your own research work!

Adding a Co-Author

Should you be wary of adding another co-author to your paper? Would it reduce the value of your paper or your contribution?

Adding a co-author does not have additional cost (except in some very rare cases((Seoul National University gives fewer points to papers with more authors in faculty appointment http://rule.snu.ac.kr/internationalRules/15.pdf))), but having another person added to your paper can add value to the quality of your work (provided that the additional co-author indeed contributes something meaningful), and having other people contribute to your work can be a start (or a continuation) of a fruitful collaboration between you and your co-authors.

That being said, a survey of 87 promotion committees (mostly from medical schools in the US) ((J. D. Wren, K. Z. Kozak, K. R. Johnson, S. J. Deakyne, L. M. Schilling, & R. P. Dellavalle, “The write position. A survey of perceived contributions to papers based on byline position and number of authors,” EMBO reports, 8(11), 988–991, 2007. https://doi.org/10.1038/sj.embor.7401095)) indicated that the perceived value of first author’s contribution decreases with increasing number of authors. Even if that were true for all other fields in other geography, I still think that the benefits of having co-authors that genuinely contribute to the paper far outweigh the tiny cost.

Is more always better? Not necessarily, but as with many things in life, one successful thing has outsized gain and can make the bulk of your success. Having more works published increases the chance that at least one will become an important work that changes your field.

Who Gets to be an Author?

Recently, many journals have made it compulsory for a paper to have CRediT (Contribution Roles Taxonomy) author statement, outlining the contributions that each author makes to the paper. The types of contributions are:

• Conceptualisation – Ideas; formulation or evolution of overarching research goals and aims.
• Data curation – Management activities to annotate (produce metadata), scrub data and maintain research data (including software code, where it is necessary for interpreting the data itself) for initial use and later re-use.
• Formal analysis – Application of statistical, mathematical, computational, or other formal techniques to analyse or synthesise study data.
• Funding acquisition​ – Acquisition of the financial support for the project leading to this publication.
• Investigation – ​Conducting a research and investigation process, specifically performing the experiments, or data/evidence collection.
• Methodology – Development or design of methodology; creation of models.
• Project administration – Management and coordination responsibility for the research activity planning and execution.
• Resources – Provision of study materials, reagents, materials, patients, laboratory samples, animals, instrumentation, computing resources, or other analysis tools.
• Software – Programming, software development; designing computer programs; implementation of the computer code and supporting algorithms; testing of existing code components.
• Supervision – Oversight and leadership responsibility for the research activity planning and execution, including mentorship external to the core team.
• Validation – Verification, whether as a part of the activity or separate, of the overall replication/reproducibility of results/experiments and other research outputs.
• Visualisation – Preparation, creation and/or presentation of the published work, specifically visualisation/data presentation.
• Writing – original draft – ​Preparation, creation and/or presentation of the published work, specifically writing the initial draft (including substantive translation).
• Writing – review & editing – Preparation, creation and/or presentation of the published work by those from the original research group, specifically critical review, commentary or revision – including pre- or post-publication stages.

The figure above is an example of CRediT author statement in a paper ((C. Luerssen, H. Verbois, O. Gandhi, T. Reindl, C. Sekhar, and D. Cheong, “Global sensitivity and uncertainty analysis of the levelised cost of storage (LCOS) for solar-PV-powered cooling,” Appl. Energy, vol. 286, p. 116533, Mar. 2021.)) where I am a co-author.

Therefore, you should have a rough idea of what being an author entails. Most journals also explicitly state their criteria for authorship. Although the criteria of authorship in different journals vary, it’s generally the following:

• To have substantial contribution to the conceptualisation, and/or((some journals require all the aspects to be fulfilled while others require just one)) the acquisition, analysis, or interpretation of data for the work, AND
• To have drafted and revised the manuscript, AND
• To have approved the final version of the paper, AND
• To have agreed to be accountable for any and all aspects of the work relating its accuracy and integrity

If someone contributes to your work, but not enough to qualify for an authorship, you can mention the person in acknowledgement. Alternatively, you can also ask the person to contribute a little bit more to qualify and add them as co-author.

However, please beware of these forms of authorship:

• Ghost authors – People who contributed but are not listed as authors
• Guest authors – People who are listed as authors because it would increase the chance of publication without sufficient contribution
• Gift or honorary authors – People who are listed as authors because of their affiliation with the work/project/lab.

While ghost authors and guest authors are (almost) universally unacceptable, many people ((21% considered honorary authorship reasonable (Vasta, 1981), and 40% of respondents from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2247376/ think that honorary authorship is common)) still tolerate and practise granting honorary authorships.

To read more on this important subject, you can check  a paper by Resnik et al. ((D. B. Resnik, A. M. Tyler, J. R. Black, & G. Kissling, “Authorship policies of scientific journals”, Journal of medical ethics, 42(3), 199–202, 2016. https://doi.org/10.1136/medethics-2015-103171)), and also ICMJE guideline on authorship matters.

Order of Authorship

Does it matter? Yes it does. The first author is generally reserved to the person who contributed the most to the work. Last person is typically reserved for the project manager, the supervisor, or the highest-ranking professor in your work/research group. These two positions are the key positions. The rest of the authors are usually ordered based on descending amount contribution, i.e. the third author is a person who contributes less than the second author, who in turn contributes less than the first author.

If you and your colleagues are working in the same research project, it is worth having a discussion regarding the output of the project: who will be writing how many papers and the authorship order of these papers. Such a discussion has the potential to save time, energy, and friendship by avoiding possible conflict when submitting a paper.

On top of determining the author order, one of the authors need to be assigned as a corresponding author. Corresponding author is the person who needs to submit the manuscript via the journal portal, who will get the reviews and the decision from the journal, and who will pay for any article processing charge (APC) (not necessary from their own pocket). Although the corresponding author is often either the first author or the principal investigator (PI)/supervisor of the project/group, there is no rule forbidding another author to be the corresponding author. And as far as I know, there is no additional prestige for being a corresponding author, except in some East Asian countries, where being a first or corresponding author are  important towards your career ((please see https://academia.stackexchange.com/questions/27553/in-chinese-academia-what-is-the-significance-of-the-corresponding-author-beyon and https://academia.stackexchange.com/questions/138017/how-is-the-corresponding-author-on-a-math-paper-typically-chosen for more discussion on the topic)).

In any case, you should check with your colleagues (and ideally also your supervisor), the common practice in your research group/field. There are always exceptions to the rule, e.g. in Mathematics and Economics where the authors are commonly listed alphabetically.

Now that you know more about how to become a co-author, get out there and learn about other people’s work. You will be surprised at how much you can contribute to others’ research and vice versa. Like what you are reading? Still unsure on how to get published? Read other articles in this series and leave your comments below!

• Getting your paper camera-ready
• Responding to reviewers (work in progress!)
• Choosing a journal (work in progress!)