Acknowledgement 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. Authorship credit should be based only on substantial contributions to

- conception and design, or analysis and interpretation of data;

- drafting the article or revising it critically for important intellectual content;

- final approval of the version to be published. Conditions 1, 2, and 3 must all be met.

Participation solely in the acquisition of funding or the collection of data does not justify authorship. General supervision of the research group is not sufficient for authorship. Any part of an article critical to its main conclusions must be the responsibility of at least one author. Editors may ask authors to describe what each contributed; this information may be published.

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 above criteria for authorship. Group members who do not meet these criteria should be listed, with their permission, in the Acknowledgments or in an appendix. The order of authorship should be a joint decision of the coauthors. Authors may wish to explain the order of authorship in a footnote.

Increasingly, multicenter trials are attributed to a corporate or corresponding author. The corresponding author ensures that all contributing co-authors and no uninvolved persons are included in the author list. The corresponding author will also verify that all co-authors have approved the final version of the article and have agreed to its submission for publication

The authors are responsible for the content of the article and for the fact of its publication. The editorial staff reserves the right to shorten and edit the articles submission.