Do women undertake interdisciplinary research more than men, and do self-citations bias observed differences?

Some studies have shown that women undertake interdisciplinary research more than men, whereas other studies have shown no difference by gender. Women have also been shown to self-cite less often than men, a difference at least partly mediated through differences in career stages and prior productivity. Existing evidence on gender-based differences in interdisciplinarity may therefore be biased. If interdisciplinarity is inferred from the disciplinary diversity of a paper's cited references, a greater share of self-citations by men could decrease their measured interdisciplinarity relative to women. Such biases could lead to erroneous conclusions, because after correcting for self-citations one might uncover that women participate in interdisciplinary research equally to, or less than, men. Given that funding for interdisciplinary research is gaining in importance, obtaining accurate measurements of interdisciplinarity by gender is highly relevant for funders so that they can take appropriate action(s) in leveling the playing field across gender. For instance, evidence suggests women are sometimes advised not to participate in interdisciplinary research due to the risk it represents for their career progression. This study shows that a paper's interdisciplinarity increases with the presence of female authors, accounting or not for self-citations in the interdisciplinarity measurement.