| Table 1: International Committee of Medical Journal Editors definition of authorship* |
| All persons designated as authors should qualify for authorship. Each author should have participated sufficiently in the work to take public responsibility for the content. |
| A person qualifies for authorship only if he or she a) has made substantial contributions to the conception and design of the study or to the analysis and interpretation of data; b) has made substantial contributions to the drafting of the article or revisions regarding important intellectual content; and c) has approved the version to be published. Conditions a), b) and c) must all be met. People who only help to acquire funding or who only collect data and those who generally supervise the research group do not qualify as authors. Any part of an article critical to its main conclusions must be the responsibility of at least one author. |
| Editors may require authors to describe what each contributed; this information may be published. |
| Increasingly, multicentre trials are attributed to a corporate author. All members of the group who are named as authors, either in the authorship position below the title or in a footnote, should fully meet the criteria for authorship as defined in the Uniform Requirements for Manuscripts Submitted to Biomedical Journals. Group members who do not meet these criteria should be listed, with their permission, under Acknowledgments or in an appendix. |
| The order of authorship is determined by the authors. Because the order is assigned in different ways, its meaning cannot be inferred accurately unless it is stated by the authors. Authors may wish to explain the order of authorship in a footnote. In deciding the order, authors should be aware that many journals limit the number of authors listed in the table of contents and that the National Library of Medicine lists in MEDLINE only the first 24 authors, plus the last. |
| *Revised in 1996 by the following attending members: Linda Hawes Clever, Western Journal of Medicine; Lois Ann Colaianni, National Library of Medicine; Frank Davidoff, Annals of Internal Medicine, Richard M. Glass, Journal of the American Medical Association; Richard Horton, The Lancet; George D. Lundberg, Journal of the American Medical Association; Magne Nylenna, Tidsskrift for den Norske Legeforening; Richard Smith, British Medical Journal; Bruce P. Squires, Canadian Medical Association Journal; Robert D. Utiger, New England Journal of Medicine. |