The explicit mention of bioethical requirements in biomedical publications involving human subjects and the inclusion of ethical criteria in the evaluation of scientific papers were investigated in a sample of journals from the Latin American and Caribbean Region. Through a selection criterion based on the indexation in databases MEDLINE and LILACS, access to complete texts and guidelines for contributors, among others, 41 scientific journals were identified, out of which 625 articles were reviewed. The results differ for drug trials (177 articles) or diagnostic clinical studies or non pharmacological treatment (448). A greater concern for ethical aspects was evident among the former (49% indicate informed consent and 46% review by ethics committee) than in the latter (32% indicate obtaining consent and 27% review by ethics committee). Also, a greater compliance with ethical regulations is observed in clinical trials phase II and III than in phase IV. The analysis of guidelines for constributors shows that in the reviewed journals editors' greatest concern refers to informed consent in the journals indexed in MEDLINE (50% asks for this requirement) and the approval by the ethics committees in the ones indexed in LILACS (in 43% it is requested). In general, the explicit compliance with ethical requirements reaches at the most 50% and there are no ethical references in almost 45% of the publications.