Does Figure-Text Improve Biomedical Article Retrieval? A Pilot Study

Graphical illustrations are often used in biomedical articles to convey statistical results, schematics, etc. They are frequently accompanied with superimposed text annotations, or figure-text. It is generally assumed that this figure-text provides information that complements associated textual metadata, such as the captions, or bibliographic citations for indexing the figures and enhanced retrieval quality. However, to the best of our knowledge nothing in the literature adequately supports the assumption of information gain. In this article, we report the results of a pilot study that compares image retrieval based on figure captions alone to that using figure-text in addition to captions. In the blind study two judges evaluated a set of figures retrieved on the topic of "lung cancer". We find that figure-text could help improve retrieval performance for specific queries.