Exploring the characteristics of special issues: distribution, topicality, and citation impact.

Special issues are a unique mode of scholarly communication designed to highlight essential or emerging research themes through high-quality manuscripts. Special issues are increasingly becoming a fixture across a wide range of disciplines. Yet whether publishing special issues is necessarily a beneficial practice remains controversial. In this paper, we explore whether the actual effect of special issues meets the academic community's expectations, which is to enhance citation impact and highlight important research topics. Our sample, which comprises all special issue articles in all disciplines published between 2008 and 2017, reveals that there has been a proliferation of special issues across countries, institutions, and journals, with some differences among the disciplines. Opportunities to appear in special issues are more given to countries/institutions that achieved the highest overall research output. The effectiveness of special issues in promoting academic development varies across disciplines and even across journals. Honing in on library and information science as a case area to explore citation impacts and the topic distribution of special issues, we find that many special issues present high-impact manuscripts, especially those of the less prominent journals. However, the issue of publishing low impact manuscripts through special issues also exists in many fields. Special issues are also more likely to publish interdisciplinary or cross-disciplinary articles and rarely discussed research themes compared to regular issues. Further, such topics are seldom explored on a large scale in the normal editions of the journal. To ensure the quality of the manuscripts, we recommend optimizing the procedures for selecting special issue topics and reviewing submissions. [ABSTRACT FROM AUTHOR]