Knowledge Production in Two Types of Medical PhD Routes - What's to Gain?

Purpose: To assess the assumption that differences exist between the traditional and publication-based PhD routes in terms of the thesis’ length and the scientific publications originating from it. Method: A retrospective comparative study on medical PhD theses offered by an online repository was performed. All free full-text medical PhD theses defended at United Kingdom institutions between 2003 and 2015 were analyzed and assigned to the traditional (TT) or publication based thesis (PBT) group. Several characteristics of theses and thesis-related articles were collected and analyzed. The thesis-related articles were investigated regarding quantity and visibility (citations, impact factor, and journal rank). Results: The theses length proved similar in PBT and TT group. PBT group included significantly more studies than TT group (mean 4.44 vs. 2.67) also reflected in significantly more thesis-related articles. The percentage of articles listed in Web of Science and published in a journal with impact factor proved significantly lower in TT compared with PBT group. On the contrary, article citations were significantly higher for TT. Both groups published similarly in high-ranked journals (Q1 or Q2). Conclusion: The research productivity originating from the PBT group was, as expected, significantly larger but not significantly more visible than those from TT group.