Thematic density of research-article abstracts: a systemic-functional account

Abstract

The abstract of a research paper is an essential component, providing key details of the full paper. Past studies often allude to their being a text type, but they also highlight variations in their organization and language features within and across disciplines. However, studies on the thematic structure of abstracts have been scarce. This study investigated whether the thematic structure of abstracts from two discipline groups – the Sciences and Humanities – differed and what these differences, if any, were. Two hundred abstracts were analyzed using Halliday’s framework. A thematic-density index was also devised to quantify the extent to which topical Themes were used to introduce ideas in the text. The results revealed that abstracts from both discipline groups shared a common thematic shape; they generally displayed a lean, linear thematic pattern with low thematic density. The groups, however, differed in the clausal distribution of topical Themes. The abstracts in the Sciences used more main-clause topical Themes and fewer embedded-clause topical Themes; the opposite was true for the Humanities abstracts. There was no significant difference in the groups’ use of subordinate-clause topical Themes. The study highlights an alternative understanding of how abstracts are both similar to and yet different from each other.

Keywords:

• abstracts
• theme
• systemic functional linguistics
• sciences
• humanities