Co – authorship

Academic authorship is used as a basis for reputation, employment, and even income. Authors are writers, but where collaboration is the norm, writing is not always seen as the only criterion for being included as an author. Collecting or analysing data, contributing to the design or simply being part of a project can also count as authorship. Who should be included on the by-line can be controversial. For this reason, most journals and scientific communities have established ethical guidelines that regulate co-authorship.

If you are a co-author you should be aware of

  • the guidelines for co-authorship that apply in your research field
  • different ethical aspects of co-authorship to help prevent misuse
  • how to handle authorship disputes

Ethical guidelines

Most journals and scientific communities have ethical guidelines that regulate authorship. Because of different types of ethical misconduct, these have been more clearly defined in recent decades.

Social sciences, humanities, law and theology

In social sciences, humanities, law and theology, it is still quite common to publish as a single author. Often the same person has formulated the problem, collected and edited the data, and written the text. Authorship relates to the concept of author rights within copyright law.

Only the persons that have contributed to documentation, analysis and writing are normally included as authors of a work. It is the act of writing that forms the basis for authorship. Therefore, a person that gives some kind of contribution to documentation, formulation of ideas for the analysis, comments on the writing, or technical help would not qualify as an author, unless the person has also contributed substantially to the writing of the work.

As a rule, the criteria for authorship in humanities, law and theology are absolute when it comes to the requirement for writing. There are large collaboration projects within these disciplines as well, but unlike those in the medical and science subjects, it is not necessary to include all contributors on the by-line. Other contributors than the writer are often mentioned in the acknowledgements. Co-authors are usually listed alphabetically.

Within social sciences, authorship is most commonly based on writing, as in the humanities. However, there may be cases where authors can be included in the author list without having written. In such instances, the area of research is more relevant to the medical and science concepts of co-authorship. For example, the American Psychological Association (APA) has guidelines for co-authorship similar to those in medicine. Authorship is not only attributed to persons writing a manuscript, but should include others who have made a substantial contribution to a study.

If you would like to learn more about this, you can find further information on co-authorship in social sciences, humanities, law and theology on the Norwegian National Research Ethics Committees' website.

Medicine: The Vancouver rules

A scientific publication in medicine will usually have multiple authors. What counts towards authorship is most often regulated by the Vancouver rules.

As an attempt to solve problems with misuse of authorship, the International Committee of Medical Journal Editors (The Vancouver Group, 1985) worked out a standardised set of criteria for authorship, the Vancouver rules. Most journals, faculties and research institutions in the field of medicine support the authorship criteria of the Vancouver Group. These rules have become an international standard for authorship in medical disciplines.

Authorship should be based on the following:

  • Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work;
  • Drafting the work or revising it critically for important intellectual content;
  • Final approval of the version to be published;
  • Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved

  (International Committee of Medical Journal Editors 2021)

All criteria must be fulfilled.

While in humanities and social sciences, authorship is based on writing a text, the Vancouver rules also include collaborative efforts as central to the notion of authorship.

Science, mathematics and technology

Natural sciences, mathematical and technological subjects do not have a universal standard for authorship, but guidelines and accepted practices are still available. There are researchers who research and publish by themselves, and there are projects that consist of several thousand members, such as those at CERN, where the list of authors can consist of a great number of people.

Although standards vary, they all require some degree of contribution and responsibility for the work. As an example, the editorial policy of the journal PNAS states: 'Authorship should be limited to those who have contributed substantially to the work.'

Some examples of guidelines in science, mathematical and technological disciplines:

  • The guidelines of the American Physics Society (APS, 2002) states that authorship should be limited to those who have made a significant contribution to the concept, design, execution or interpretation of a research study. Individuals who have contributed to the study in other ways should be acknowledged, but not identified as authors.
  • The American Chemical Society (ACS, 2011) has criteria for co-authorship similar to those in physics. The ACS specifies that authors share responsibility and accountability for the results presented in a scientific work.
  • The guidelines of the American Mathematical Society and the American Statistical Association (AMS, 2005; ASA, 1999) state that all authors should have given significant intellectual contributions to the work to be included on the author list. There can be exceptions to this rule, but these have to be specifically explained. Mathematical publications usually list the authors alphabetically (the Hardy-Littlewood rule). This rule states that anyone that joins collaboration in good faith will be listed equally as an author, regardless of the relative contributions they end up making.
  • Guidelines for authorship in biology are closely tied to the guidelines for biomedical publishing (the Vancouver rules). Authors should make a substantial intellectual contribution to the work in question. Administrative and economic responsibility alone do not qualify for authorship.


Physics is one of the areas where the Vancouver protocol does not have a very strong foothold, simply because the work is so different from that of many other research fields. There can be years of work behind the final results and conclusions which lead to a written article. Håvard Helstrup, Professor, Relativistic Heavy Ion Physics (ALICE/CERN), explains:
'The tradition of co-authorship in experimental physics has its roots in the line of work within its field. First you establish an experiment which often includes construction of new equipment, then you measure and store results, and then you look at the results. The results are then systemized and presented as a final result. This line of work has its roots way back to people like Galileo Galilei, who first constructed the telescope, then placed it towards the stars and noted his observations, and then, finally, he published his observations. Let us use ALICE as an example. They started the planning of the experiment in 1990 and in the years to follow a lot of planning and design was done. From 2000 to 2009 the experiment was constructed, built and installed, and in the fall of 2009 the first measures and results were published. Simulations were done from people with computer skills, design and putting it together was done by people with knowledge in electronics, and everybody had to contribute in the day-to-day running of the experiment. The final analysis is verified by experts in modeling and theory. Often it is this last group that does the actual writing, but if no one built the experiment there simply would be no results to analyze…. ALICE has about 1000 members.'

Central questions of co-authorship

As the importance of authorship has grown, so has the average number of authors contributing to an article. Research has become more interdisciplinary and international, and is often carried out as cooperation projects with many participants.

Examples of unjustified authorship:

Gift authorship: a person that does not fulfill the criteria for co-authorship, but has such a strong position within the research group that he/she can expect or demand authorship.

Guest authorship: prominent people that are asked or pressurised to be on the by-line because this is expected to strengthen the project and the chances of publication. For the same reasons, persons can also be put on the by-line without being asked.

Ghost authorship: persons that fulfil the criteria for authorship, but are left out of the author list, either with or without their consent. This is especially a problem with regard to authority within a research community. A supervisor might not always protect the rights of the younger researchers in the group.

Some central questions concerning co-authorship:

  • Why is it important to be credited as an author?
  • What kind of contribution should qualify for authorship?
  • What should be the order of authors on the by-line of an article?

The listing of authors on the by-line of an article can lead to conflict. The leader of a project may decide the order of authors. Young researchers do not always have much to say in the matter, and their contribution to the work may not be mentioned.

Conflicts concerning co-authorship are not uncommon. A study of articles in six prestigious medical journals found that every fourth article had at least one unjustified author, while every tenth article failed to include authors that should have been on the list (Wislar et al., 2011). Another study has shown that more than two-thirds of corresponding authors disagreed with their co-authors regarding the contribution of each author (Illakovac et al., 2007).

Authorship is about taking responsibility for one's own work. Co-authors should be able to support the main results presented in a paper. Reputations can be discredited if people’s names appear on a paper they have neither written nor reviewed and approved. Additionally, authors are expected to keep the research data that the study is based on for later examination, and should provide information about any commercial or non-commercial conflicts of interest.

Co-authorship influences the financing of research. In Norway, the government allocates money to research institutions based on authorship contribution. The money given for a publication is divided between the authors, and some measures have been taken to reward international cooperation. Read more about the Norwegian Cristin system for further information.

The main problem of co-authorship is that some people may have contributed to the publication, but not enough to be on the by-line as an author. This has led to a suggestion to establish a new system based on contribution as well as authorship. Such a system would specify the individual contribution, and this information would be made available in the published work. One suggestion is that contributors that do not fulfill the criteria for authorship should be mentioned in the acknowledgements instead.

This contribution system has so far not been a success: only some journals use it, and since there is no international classification system to describe different types of contributions, other contributors than authors are not credited for the work.


A PhD candidate has been working on an article in collaboration with her supervisor and other candidates. What to do if there is a dispute over co-authorship?
All the candidates and the supervisor have contributed to the writing, reviewing and collecting of data, and are therefore all listed as co-authors on the by-line of the article.
The article is in the process of being submitted to a prestigious journal, when the leader of the research group (Professor A) contacts the supervisor. Professor A takes it for granted that he will be on the by-line of the article. The authors will be listed alphabetically, which means that Professor A will be the first author on the by-line. The PhD candidate, who has done most of the work, will be listed as author number three.

Professor A has several arguments for this:

  • He is an experienced researcher in great demand in the field.
  • He has previously published several articles in the journal, and also knows one of the editors.
  • Putting him on the author list might make it easier to get the article accepted in the journal.
  • He also argues that since the project has financed his work on the article, it is only reasonable that he should be on the author list.

In his case: What do you think should be the criteria for authorship? What is the fairest way to list authors on the by-line of the article?

Handling authorship disputes

Guidelines governing co-authorship vary between disciplines and even research groups. However, there are some general principles that you should be aware of in order to avoid authorship disputes, and also to know how to resolve such disputes if they occur.

There are two types of authorship disagreement:

  1. Disputes: These are usually about whether someone’s contribution is substantial enough to be included on the by-line, and can therefore be a question of interpretation. Disputes can most often be solved by negotiation with the other members of the research group.
  2. Misconduct: These are cases where someone is proposing listing of co-authors in a manner that does not conform with the guidelines of the journal. These kinds of disputes can be more difficult to solve: if you decide not to act, this could make you a party to unethical conduct. On the other hand, acting might damage your future career. One solution could be to explain to your co-authors that the author list does not follow the guidelines of the journal, involving a risk that the authors could be considered guilty of misconduct.

Note the following tips to help prevent authorship disputes:

  1. Start discussions at an early stage: Start discussing who will be on the author list and the order of authors at the point when you are planning your research, and keep on discussing these issues throughout the process of writing and submitting the manuscript. There may be changes in which people should be considered as authors and their position on the by-line during a research project. The research group should therefore try to have a common understanding of what kind of work merits authorship and who has the main responsibility for writing, submitting and editing the work.
  2. Address emotional issues: Group dynamics and interpersonal issues can have a huge impact on a project. People that spend a lot of time on a project have strong feelings about how the results should be interpreted and presented, and different people may have different interpretations of how things should be done. Often it will be useful to address problems directly by acknowledging disagreements, setting boundaries and trying to find common ground. Sometimes it might be necessary to involve a neutral third party in the process.
  3. Sign a formal agreement: If possible, authorship should be decided before you start working on an article. Every team should have a written agreement that states the roles of the different contributors.
  4. Be consistent: Criteria for authorship and order on the by-line should be consistent within the research group, and also with the norms of authorship within the community.
  5. Know the guidelines: You can help encourage a good culture of co-authorship by being aware of journal-specific guidelines, as well as general guidelines of co-authorship within your field.
  6. Take responsibility: All authors should check the final version of a publication before it is submitted and it should be possible to withdraw your name if you disagree with the interpretation of the results. If you have been put on the author list without your consent, or if you have been wrongly omitted, you should inform the other authors. In some instances, it is possible to contact the journal to ask for a correction after an article is published, but an editor is unlikely to add your name on the by-line unless all authors agree.

Academic Integrity

The notion of academic integrity is the cornerstone of all questions of authorship; the 'fundamental values of academic integrity', according to the International Center for Academic Integrity (2014) are as follows:


Honesty lies at the bottom of all this, and acts as a necessary prerequisite for trust, fairness, respect and responsibility. Being honest in your research sends a message that any falsification of data, lying, cheating, theft or other dishonest behaviour is unacceptable. Honesty begins with the individual researcher; it begins with you. Correct citation of your sources is one important way of being honest; but remember that honesty is not a black and white matter! Even if using a secondary source is perfectly acceptable in cases where it is impossible to get hold of the primary source, referring to a secondary source instead of the usual original source may also be a case of too much honesty, or at least an example of academic laziness.


When honesty is established as a core value, trust is a natural successor. Trust comes over time and is built on more than pure words. Trust is also a reciprocal notion; being trustworthy and trusting others go hand in hand. Only with trust can you allow yourself to build your research on that of another, and trust is thus a foundation of all academic work. Trust enables you to collaborate and share, and to present new ideas without the fear that someone will steal your work. But remember your own voice in this choir; the so-called 'Chinese whispers effect' can arise from too much trust in research. If you are keen to use primary sources in your research, you can show that you are trustworthy by not blindly trusting your supervisor's interpretation of a theory, and demonstrating that you have understood the value of using the primary source.


Important components of fairness include predictability, transparency and reasonable expectations. Fairness is important with regard to the assessment of work, and is of course a key element in building trust between student and university. You act fairly when you do your own work honestly, when you cite your sources, when you act in accordance with the policies of your university and research community, and when you maintain your university's reputation. You are also acting fairly when your reaction to dishonesty is consistent. Fairness in research is something that goes beyond data analysis and article writing, it is the way in which you treat your whole community, your fellow researchers, your students and the administration of your university.


Scholarly communities can only evolve in an environment where there is respect for their members and for the diverse and sometimes contradictory opinions that can arise. Active learning environments typically encourage engagement and debate; disagreements over ideas are tempered by respect for those who voice them. Respect goes both ways; you need to respect yourself as well as others. Respecting yourself means dealing with academic integrity.


Being responsible means standing up to wrongdoing and serving as a positive example. Being responsible means that you regard yourself as accountable for your own actions. Being responsible also means that you hold others accountable when they fail to act in accordance with the values of the group. Responsibility for sticking to the values of academic integrity is both shared and individual.

The five key values have at least one thing in common; they require courage to act by them. Courage should not be underestimated here, even if it is less of a 'value' and more of a quality or capacity. Courage could be defined not as lacking fear, but as the ability to act according to your values despite fear. Courage, like intellectual capacity, can only develop in an environment where it is tested. As a member of an academic community, you need not only to learn to make honest decisions, but also to display the courage to follow these decisions with action.


'Courage' has been added to the original list of the first five values as a reminder that it sometimes can take a bit of personal commitment to act in accordance with the five key values. What is regarded as ethically correct research will differ from subject to subject, and we cannot provide information on all subjects on this site. Please refer to the Norwegian National Research Ethics Committees (Etikkom) for the rules governing your subject area.


Ilakovac, V., Fister, K., Marusic, M., & Marusic, A. (2007). Reliability of disclosure forms of authors' contributions. Canadian Medical Association Journal, 176(1), 41-46.

International Center for Academic Integrity (2014). The fundamental values of academic integrity. International Center for Academic Integrity, Clemson University. Available from:

Wislar, J. S., Flanagin, A., Fontanarosa, P. B., & Deangelis, C. D. (2011). Honorary and ghost authorship in high impact biomedical journals: a cross sectional survey. British Medical Journal, 343, d6128.