According to table 2, the overall scores of publication ethics, impact factor, and indexing level in the English language journals were significantly higher than those in the Farsi language ones, but their ranking was identical. Table 2 Comparison of the overall scores of publication ethics, ranking, impact factor, and indexing level between the English and Farsi journals There

was a significant positive correlation between the overall score of the publication ethics of the journals and their ranking (P<0.001) and impact factor according to the Kendall correlation (P=0.02). Furthermore, there was a significant difference Inhibitors,research,lifescience,medical between the overall score of publication ethics in different levels of indexing using the ANOVA (P<0.001). Discussion In this study, we evaluated the quality of publication ethics in the instructions Inhibitors,research,lifescience,medical to the authors of Iranian journals of medical sciences. Inhibitors,research,lifescience,medical As was demonstrated, the most frequently mentioned principles of publication ethics

in the instructions to authors were “redundant publication” (85%), “author’s responsibility for data accuracy” (83.8%), “aim and scope” (81.9%), “principles of medical ethics in the use of human samples” (74.4%), “review process” (74.4%), and Inhibitors,research,lifescience,medical “copyright” (71.2%). The Iranian journals of medical sciences, included in the present study, were of high quality in terms of editorial leadership

vis-à-vis the aforementioned ethical considerations as expressed in their instructions to authors. Nevertheless, the editors need to upgrade their instructions to authors regarding “principles of advertising” (1.2%), “authorship criteria” (15%), “integrity in reporting clinical trial results” (30.6%), “conflict of interest” Inhibitors,research,lifescience,medical (53.8%), and “principles of medical ethics in the use of animal samples” (65.6%). One of the most frequently mentioned ethical considerations was “redundant publication”, unless which was significantly of a higher frequency in the English language journals than in their Farsi language counterparts (P<0.01). Kim et al.7 in Korea, showed that 5.93% of the index articles were associated with 29 duplicate articles, which exceeded expectations. Thus, they suggested that researchers receive further education on publication ethics. One way to overcome such a problem is to augment instructions to authors of journals. In a similar vein, a study by Kitagawa,8 in Japan suggested that raising awareness about duplication publication among researchers requires the understanding of publication ethics.