For human or animal experimental investigations, appropriate institutional review board or ethics committee approval is required, and such approval, including the official approval code, should be stated in the methods section of the manuscript. For those investigators who do not have formal ethics review committees, the principles outlined in the Declaration of Helsinki should be followed (World Medical Association. Declaration of Helsinki: ethical principles for medical research involving human subjects ).

For investigations in humans, state explicitly in the methods section of the manuscript that informed consent was obtained from all participating adults and from parents or legal guardians for minors or incapacitated adults, together with the manner in which informed consent was obtained (ex. oral or written). The privacy rights of human subjects must always be observed.

For work involving animals, the guidelines for their care and use that were followed should be stated in the methods section of the manuscript. For example, the ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments Guidelines). For those investigators who do not have formal institutional guidelines relating to animal experiments, the European Commission Directive 86/609/EEC for animal experiments should be followed and the same should be stated in the methods section of the manuscript.