Equal does not mean identical
Co-first status recognises two or more people whose overall scholarly contributions are judged equivalent. Their tasks need not mirror one another: one researcher may have led conception and fieldwork, while another led analysis and drafting. Each person must still satisfy the applicable authorship criteria, approve the manuscript and accept accountability.
The designation only partly corrects a linear byline. Databases may display one name first, shorten citations or omit footnotes. A contribution statement, an agreed ordering rationale and technical checks are therefore all needed. An unexplained asterisk is not enough.
Choose and record a neutral ordering principle
Submission systems still require a sequence. Options include alphabetical order, a documented draw, rotation across genuinely connected papers or a reasoned small difference in the contribution as a whole. Agree the principle before submission. Senior pressure must not become an invisible rule.
Alphabetical order is neutral only when explicitly agreed and not misleading in the field. Rotation relies on realistic future work and cannot promise credit regardless of contribution. A draw should be witnessed and recorded. None of these devices changes the public statement of equal contribution.
CVs, funding applications and institutional profiles should state equal first authorship where the format permits. The person occupying the first technical position should not present it elsewhere as evidence of a larger contribution.
Check journal implementation before uploading
Read the author instructions, submission form and recent published examples. Some journals accept a byline footnote; others rely on contributor statements or limit the number of equal contributors. If the platform cannot represent an allowed statement, ask the editorial office and retain its response.
Keep the cover letter, manuscript and submission metadata consistent. Explain both equivalence and ordering briefly. Every author confirms the representation. Revisit the statement after peer review if substantial new work has been added. A platform limitation does not authorise a false account; it requires an agreed editorial solution.
Audit each public representation after publication
Check the note in PDF, visible HTML, contributor information and exported citation metadata. Indexing services do not always retain equality markers. Record the publisher's canonical version and report omissions that the publisher can correct. Do not silently alter bibliographic facts in a repository copy.
ORCID and institutional systems may permit an explanatory note. Keep it separate from the article title and preserve the canonical author sequence. Where evaluation systems ignore equal contribution, provide the publisher's statement as evidence rather than inventing an alternative citation.
Make sure accessibility is not overlooked. A symbol needs text, should link to its explanation and must not rely on colour. In a long author list, the note should identify precisely which names share the contribution.
Reassess equality when revision changes the work
Additional experiments, new analysis or extensive redrafting can shift contributions. Update the matrix and discuss whether equivalence still holds. An early agreement is not property that can never change, yet revision requires reasons, evidence and a fair opportunity to respond.
The authorship criteria are the prerequisite. The author-order decision record structures discussion. More material appears in the publication ethics hub. The one foundation route is the guide to documenting review evidence.
Record shared decision-making as well as task allocation. Equality may rest on both researchers shaping the question, interpretation and revision response even where individual work packages differ. A simple division into “experiments” and “writing” is uninformative if it leaves result checking and intellectual accountability unexplained.
Plan outward communication. Press material, laboratory pages and conference slides should not spotlight only the technically first name. Method and data enquiries may go to different contributors without diminishing equal status. Corresponding authorship is primarily a contact and coordination function, not an automatic higher rank.
For three or more equal contributors, confirm journal support and ask whether the statement remains informative. Describe each person's complementary work separately. A broad equality note can otherwise hide differences and weaken accountability.