Context: Although criteria justifying authorship of scientific medical articles have been formulated, it is not well known how authorship is established in practice.
Objectives: To assess the criteria for authorship used by authors of original articles in Nederlands Tijdschrift voor Geneeskunde (NTVG, the Dutch Journal of Medicine), and to determine whether the criteria for authorship of the International Committee of Medical Journal Editors (ICMJE) are known and applied.
Design: Survey questionnaire.
Setting: Editorial office of the NTVG.
Participants: All 450 authors of 115 original articles published in 1995.
Main outcome measures: Author's contribution to study design, material, collection of data, statistics, and writing.
Results: Of 362 forms returned, 352 could be analyzed (78.2% response rate). The 5 questions most frequently answered affirmatively were ICMJE criteria: critical reading (86.1 % of the authors), approval of the final version (84.7%), study design (74.7%), study conception (64.2%), and revision (63.4%). Authors rated their contribution 2 points higher than did their coauthors. Interestingly, 64% of the respondents met the ICMJE criteria, although 60% of the respondents did not know them.
Conclusion: Authorship was mostly in accordance with ICMJE criteria although many authors were not familiar with them.