Virtually every peer reviewed journal, and certainly all BMJ Journals, including the Archives of Disease in Childhood, have statements that govern the declaration of competing interests. A competing interest exists “when professional judgment concerning a primary interest (such as patients’ welfare or the validity of research) may be influenced by a secondary interest (such as financial gain or personal rivalry)” (see http://resources.bmj.com/bmj/authors/checklists-forms/competing-interests). Most of these rules are clear: if an author has received a fee for consulting or speaking, or reimbursement for attending a symposium from an organisation that may in any way gain or lose financially as the result of a publication, the author must declare a competing interest. Similarly, authors should always declare the sources of funding for research. In many respects, these are easy rules – virtually no one would dispute that speaking fees or stock options are examples of conflicts and should be declared and noted at the time of submission. Influential editors have argued that transparency and full disclosure are a prerequisite for publication.1^–3

Journals must rely on authors to declare competing interests. …