This corpus-driven study on reflexive metadiscourse in Spanish research articles from three disciplines (Medicine, Economics and Linguistics), points out that scientific writers from Economics and Medicine use significantly less metadiscourse markers than their Linguistics counterparts. There are also statistically important differences between the three corpora as to various functional categories: self-mentions, relational markers, directives, discourse verbs, and code glosses. This suggests that this genre greatly differs in terms of the way and degree to which scholarly writers from different disciplines are expected to signify their authorial presence, interact with their audience and direct the reader.