The fourth authorship criterion from ICMJE
In August 2013 the ICMJE introduced a fourth authorship criterion to supplement the existing three criteria. This has caused some misunderstandings around the world, and I will therefore try to clarify the meaning of this new authorship criterion. The new criterion concerns articles with many authors meaning where the responsibility should be placed if errors are suspected or if fraud may be a possibility. The fourth authorship criterion does not state, that all authors are responsible for all content in the paper. By contrast, the meaning of the fourth authorship criterion is, that all authors should be able to help solve a question on irregularities in the article by pointing to the specific person on the author list which has been responsible for a certain part of the product.
In this context it is also important to emphasize, that you are not responsible for all content in an article simple because you are one of many authors. It is also the Vancourver-group’s clear position that there is no such thing as a senior author when talking about author’s responsibilities. A senior author or a corresponding author or any other author, do not have special responsibilities when it comes to the integrity of a scientific paper. All authors are equally responsible under the authorship criteria, i.e. one author is responsible for his own contributions and not for the rest. If hypothetically a senior author should be held more responsible than other authors, that would automatically mean that the other authors had less responsibility, and this is not the way it should be. Therefore, all authors are equally responsible, but very importantly only for their own contributions.