The International Society for Medical Publication Professionals (ISMPP) runs a certification scheme by which medical writers and publication planners can demonstrate their competence and, in particular, their knowledge of publication guidelines. Those who have passed an exam are entitled to use the initials Certified Medical Publication Professional (CMPP) after their name. ClinicalTrials.gov is a trial register sponsored by the United States National Library of Medicine. Medical Journal Editors announced that trial registration would be a condition for publication in their journals after July 2005. A few predatory publishers, not content with trying to lure authors with journal titles that are confusingly similar to existing, reputable journals, have hijacked genuine journals and produced predatory clone websites. Committee on Publication Ethics (COPE) was established by journal editors to provide help with ethical issues. The committee discusses cases anonymously and then offers advice. Some journals ask reviewers to indicate whether a submission should be accepted with minor modification or only after substantial revision.