The cover letter must include a statement declaring the study complies with the current ethical considerations. Authors reporting the experimental studies on human subjects must include a statement of assurance in the Materials and Methods section of the manuscript that:

1. The informed consent was obtained from each participant included in the study,
2. The study protocol is consistent with the ethical guidelines of the 1975 Declaration of Helsinki as reflected in a prior approval by the institution's human research committee.

Every experimental or clinical study may raise controversial ethical issues (e.g., Institutional Ethical Approval to study on animal or human subjects). Thus, the journal editorial board expects all authors, reviewers, and editors to consider the COPE, ICMJE and Equator Network’s reporting guidelines in medical ethics plus the scientific writing. If any, authors should state related declaration(s), otherwise, the following sentence should be given: “None be declared”.