Scientific peer review is the process by which studies get published in journals. In order to increase the veracity of the journal, all studies in it are sent to other scientists who are experts in that field. Those experts review the paper to ensure that everything is technically correct and the claims that were made are backed up with data. As a concept, there are no real cons to peer review other than it taking time. In terms of pros it increases the reputation of the authors and journal bidirectionally if the study is of high quality. In fact, peer review is like the quality control process of the science factory. It has been shown not to work in certain cases however, such as that of the Bogdanoff twins wherein they were awarded PhDs in physics despite gibberish thesis papers.
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