Determining authorship in multicenter trials: a systematic review

The practical and ethical issues in determining authorship in multicenter trials raise significant and unique challenges. This systematic review examines methods of assigning authorship in multicenter clinical trials. A literature search (October 2009) was conducted to identify articles with the terms 'authorship' and 'clinical trial,' 'multicenter' or 'multicentre.' Abstracts were reviewed for potential relevance and the complete manuscript was obtained where indicated. Additional articles were identified by a review of the reference list from sourced articles. Methods for determining authorship were reviewed in terms of practicality, fairness and the time course for decision-making. Eight methods for determining authorship were identified: four used a scoring system, two articles contained guidelines with reference to scoring systems and two articles outlined general guidelines. All methods attempted to provide a fair and practical approach and appeared to achieve this to varying degrees. No one method was applicable across all multicenter trials. The authors propose a guide for determining authorship based on the methods identified and the number of collaborators and anticipated publications. For smaller collaborative groups (e.g. <10 persons), byline inclusion of all authors based on relative contributions is recommended. For larger collaborations (e.g. ≥ 10 persons), authorship guidelines should be explicit from the outset of the trial with consideration of relevant scoring systems.