Interdisciplinary research will never take off: empirical results based on theoretical insights

<ns3:p> Background The focus on either epistemological or (demand and supply) institutional obstacles to interdisciplinary research (IDR) in higher education precludes the empirical evaluation of their relative importance and the empirical suggestion of the main policies to cope with these obstacles. Methods This paper characterises IDR in terms of What, How, Where, Why and Who. It presents <ns3:italic>theoretical</ns3:italic> insights about internal obstacles ( <ns3:italic>epistemological</ns3:italic> in What and How arising from cognitive issues) vs. external obstacles ( <ns3:italic>institutional</ns3:italic> in Who due to lack of demand by journals or lack of supply by scientists) to the possible future achievements of IDR. It constructs a representative dataset on the interdisciplinary literature (Scopus articles with “interdisciplinary” or “interdisciplinarity” in title and abstract to measure genuine and trendy IDR, respectively) based on the average citations per article and H-indexes for authors across 25 disciplines from 2001 to 2020. It applies fixed-effects panel-data estimations with discipline dummy variables to the numbers and percentages of IDR articles in terms of trends and linkages with citations and H-indexes. Results This paper <ns3:italic>empirically</ns3:italic> shows that (non-existent) epistemological obstacles &lt; (non-significant) institutional obstacles due to lack of demand &lt; (significant) institutional obstacles due to lack of supply, where linkages with abstracts (trendy IDR) &lt; linkages with titles (genuine IDR). It reviews the main <ns3:italic>theoretical</ns3:italic> policies to deal with obstacles to IDR. Conclusions This paper reviews the main <ns3:italic>theoretical</ns3:italic> policies to deal with obstacles to IDR, by <ns3:italic>empirically</ns3:italic> concluding that, because of rooted views and vested interests within disciplines, the long-run public institutional changes (e.g., top-down regulations such as applying a net per-capita per-year H index with extras for IDR scientists) needed to provide incentives to the short-run private cognitive changes (e.g., bottom-up scientific collaborations) are unlikely: 10% of trendy and genuine IDR articles are expected in 2030 and 2334. </ns3:p>