Authorship regulations in performance-based funding systems and publication behaviour – A case study of German medical faculties

This article investigates whether German medical faculties with different authorship regulations show different publication patterns. In 2004, the German Research Foundation (DFG) suggested a formula consisting of third-party funding, the cumulated JIF of publications and a fractional counting of publications to counteract the increasing inflation of author counts in medical publications. Whereas the third-party funding and the JIF are generally used in research evaluation without variation, the authorship regulation differs among medical faculties. We therefore compare medical faculties using the DFG model - to credit first and last authors with a higher share than middle authors - with those faculties that apply whole counting. We answer the question whether the faculties with the different counting methods also show different authorship and publication behaviour, i.e., authorship and collaboration patterns, the choice of journals (JIF level) and the citation impact (share of highly-cited papers). Findings indicate a clear trend of increasing co-author numbers and of middle-author papers, irrespective of authorship regulation. Publications with DFG model have only a slightly lower average author count and lower shares of middle-author papers than whole-counted publications. Our findings suggest that the DFG regulation has not resulted in a reduction of the number of authors, which was a major aim. Moreover, the results show that the use of whole counting goes together with higher productivity and higher impact, which may be a good reason to select that model.