In the context of research papers, the term “co-author” is used to describe all the authors besides the lead author. Usually, when several authors work together to complete a research project, they are called co-authors. For example, if a research paper has four co-authors, it means that the paper has four authors besides the lead author.
The lead author is generally the person whose name appears first in the list of authors. They:
- Take overall responsibility for the manuscript,
- Are usually the corresponding author i.e. someone who takes charge of getting approval from all the other authors and communicating with the journal,
- Are typically the first author of the paper, which means he/she has made the most significant contribution to the research, and has also written and edited a major part of the work.
Although the lead author does most of the work, the other co–authors participate in the project at various stages and ensure that the study is completed successfully. Thus, the lead author is the person who ensures that the entire study gets completed and is responsible for writing the manuscript. The other co–authors help the lead author by looking after certain aspects of the project like conducting experiments or analyzing data.
Typically, when multiple authors are involved in a project, the lead author is the person who is the most senior of all the authors and has more experience or expertise in the field. In other words, it is the person who is most suited to supervise the project.
According to the ICMJE guidelines, anyone who fulfils all of the following criteria can be an author:
- Contributes significantly to the conception, design, execution, and/or analysis and interpretation of data,
- Participates in drafting and/or revising part of the manuscript for intellectual content,
- Approves the version to be published,
- Agrees to be accountable for all aspects of the work.
The order in which the authors are listed in the paper is usually based on their relative contribution to the paper. Therefore, the first author is the person who has made the greatest contribution and has been most involved in the study. The other authors are then listed in the order of who provided the greatest assistance. Regardless of their order, their roles are usually specified in the ‘author list’ of the paper for full transparency.
