An “author” is generally considered to be an individual who has made a significant intellectual contribution to the study.
According to the guidelines for authorship established by the International Committee of Medical Journal Editors (ICMJE), "All persons designated as authors should qualify for authorship, and all those who qualify should be listed." Four criteria must all be met to be credited as an author:
■ Substantial contribution to the study conception and design, data acquisition, analysis, and interpretation.
■ Drafting or revising the article for intellectual content.
■ Agreement to be accountable for all aspects of the work related to the accuracy or integrity of any part of the work.
■ Approval of the final version. The following are some general guidelines, which may vary from field to field:
■ The order of authorship should be "a joint decision of the coauthors".
■ Individuals who are involved in a study but don't satisfy the journal's criteria for authorship, should be listed as "Contributors" or "Acknowledged Individuals". Examples include: assisting the research by providing advice, providing research space, departmental oversight, and obtaining financial support.