First Author vs Second Author vs Last Author
In many biomedical papers, the first author usually made the largest contribution to the work and the writing, the last author is often the senior or supervising author, and middle authors are listed in order of contribution or alphabetically, depending on convention. These are conventions, not rules, and they vary by field, country and team.
Typical meanings
| Position | Common meaning (varies) |
|---|---|
| First | Did most of the work and writing; often conducted the study |
| Second | Substantial contributor, sometimes second-largest contribution |
| Middle | Contributors of decreasing contribution, or by role |
| Last | Senior author, supervisor, principal investigator who conceived or oversaw the work |
| Corresponding | Handles communication and takes administrative responsibility (can be any author) |
ICMJE does not specify order; it states that authors should decide order together. Some groups use alphabetical order or explain order in a contribution statement.
How to agree order
- Discuss at the start and revisit if roles change.
- Base order on actual contributions to design, work, analysis and writing.
- Write the agreement in an email or a document.
- Use "equal contribution" notes where appropriate (see Can Two Researchers Share First Authorship?).
- If you cannot agree, seek advice from a neutral senior colleague or your institution.
Illustrative example
Invented for teaching. A student leads data collection and drafts the manuscript, a registrar supervises the analysis, and a consultant conceived the study and supervises. The team agrees on student as first author, registrar as second and consultant as last and corresponding author, and records this in a short email.
Common pitfalls
- Assuming everyone follows the same convention: check the journal and field.
- Changing order late without agreement.
Key takeaways
- Order conventions vary: agree explicitly.
- Contributions, not titles, should guide order.
References and further reading
Related reading
This page is general educational information about research methods. It is not medical, legal or regulatory advice; follow your institution's ethics board and your target journal's instructions.