Consistency and validity of interdisciplinarity measures

TL;DR

This paper systematically reviews existing measures of interdisciplinarity, revealing their inconsistencies and questioning their validity, and emphasizes the need for new, more appropriate measurement approaches for this complex concept.

Contribution

It provides a comprehensive analysis of current interdisciplinarity measures, highlighting their flaws and advocating for the development of novel, more valid measurement tools.

Findings

Current measures are inconsistent and often deviant in results.

Existing measures are confusing and unsatisfying for capturing interdisciplinarity.

There is a need for new measurement approaches for complex, multidimensional interdisciplinarity.

Abstract

Measuring interdisciplinarity is a pertinent but challenging issue in quantitative studies of science. There seems to be a consensus in the literature that the concept of interdisciplinarity is multifaceted and ambiguous. Unsurprisingly, various different measures of interdisciplinarity have been proposed. However, few studies have thoroughly examined the validity and relations between these measures. In this study, we present a systematic review of these interdisciplinarity measures and explore their inherent relations. We examine these measures in relation to the Web of Science journal subject categories. Our results corroborate recent claims that the current measurements of interdisciplinarity in science studies are both confusing and unsatisfying. We find surprisingly deviant results when comparing measures that supposedly should capture similar features or dimensions of the concept of interdisciplinarity. We therefore argue that the current measurements of interdisciplinarity should be interpreted with much caution in science and evaluation studies, or in relation to science policies. We also question the validity of current measures and argue that we do not need more of the same, but rather something very different in order to be able to measure the multidimensional and complex construct of interdisciplinarity.