All authors must state any financial and personal links they have with others or organizations that may improperly affect or bias their work. Employment, consultancies, stock ownership, honoraria, paid expert testimony, patent applications and registrations, and grants or other support are all examples of potential clashing interests.

Authors must disclose any conflicts of interest in two places:
1. A brief statement of conflict of interest in the title page file (if double anonymized) or the manuscript file (if single anonymized). If you have no interests to disclose, please state the following: 'No declarations of interest'.

2. Extensive disclosures on a separate Declaration of Interest form that becomes part of the journal's official records Potential conflicts of interest must be stated in both locations for the information to match.