[Plagiarism and duplicate publications in the medical literature: scope of the problem, risks, warning signs, and prevention strategies].

Plagiarism and duplicate publications pose a persistent threat to the integrity and credibility of the medical literature. Despite the widespread adoption of ethical rules, international guidelines, and detection software, these practices remain prevalent in medical research, and their scope continues to expand. Their consequences extend beyond damaging the reputation of researchers and journals. They can bias the scientific evidence base, distort the outcomes of systematic reviews and meta-analyses, artificially inflate researchers' academic achievements, waste editorial and peer-review resources, and undermine public trust in medical research. This review article outlines the scope of the problem, its typologies, and its inherent dangers. The article also highlights warning signs that can help editors, reviewers, and readers identify suspicious cases both pre-publication and post-publication. Finally, the review outlines recommended strategies to prevent the phenomenon, including research ethics education, adherence to international scientific publishing guidelines, transparent reporting, and strengthened institutional oversight mechanisms. Raising awareness of these issues and fostering a culture of scientific integrity are essential prerequisites for mitigating this phenomenon and reinforcing the quality, credibility, and reliability of the medical literature.