Title: On the peer review reports: It's not the size that matters ... really?

Abstract: Scientometers and sociologists of science have spilled much ink on the topic of peer review over the past twenty years, given its primordial role in a context marked by the exponential growth of scientific production and the proliferation of predatory journals. Although the topic is addressed under different prisms, few studies have empirically analyzed to what extent it can affect the quality of publications. Here we study the link between the length of reviewers' reports and the citations received by publications. To do this, we used data from the Publons database (58,093 peer review reports). We have adjusted this sample to match the WoS database structure. Our regression results show that peer review positively affects the quality of publications. In other words, the more indepth (longer) the referees' reports are, the greater the publication improvements will be, resulting in an increase in citations received. This result is important from both the point of view of reviewers and that of journal's chiefseditors. Even if it is not a remunerated activity, it is important that it be more valued at least within the framework of research evaluation exercises, given its positive impact on science.