INTERNATIONAL JOURNAL OF HEALTH GEOGRAPHICS MacEachren et al. International Journal of Health Geographics 2010, 9:23 http://www.ij-healthgeographics.com/content/9/1/23 Open Access RESEARCH © 2010 MacEachren et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Com- mons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduc- tion in any medium, provided the original work is properly cited. Research HEALTH GeoJunction: place-time-concept browsing of health publications Alan M MacEachren*, Michael S Stryker, Ian J Turton and Scott Pezanowski Abstract Background: The volume of health science publications is escalating rapidly. Thus, keeping up with developments is becoming harder as is the task of finding important cross-domain connections. When geographic location is a relevant component of research reported in publications, these tasks are more difficult because standard search and indexing facilities have limited or no ability to identify geographic foci in documents. This paper introduces HEALTH GeoJunction, a web application that supports researchers in the task of quickly finding scientific publications that are relevant geographically and temporally as well as thematically. Results: HEALTH GeoJunction is a geovisual analytics-enabled web application providing: (a) web services using computational reasoning methods to extract place-time-concept information from bibliographic data for documents and (b) visually-enabled place-time-concept query, filtering, and contextualizing tools that apply to both the documents and their extracted content. This paper focuses specifically on strategies for visually-enabled, iterative, facet-like, place-time-concept filtering that allows analysts to quickly drill down to scientific findings of interest in PubMed abstracts and to explore relations among abstracts and extracted concepts in place and time. The approach enables analysts to: find publications without knowing all relevant query parameters, recognize unanticipated geographic relations within and among documents in multiple health domains, identify the thematic emphasis of research targeting particular places, notice changes in concepts over time, and notice changes in places where concepts are emphasized. Conclusions: PubMed is a database of over 19 million biomedical abstracts and citations maintained by the National Center for Biotechnology Information; achieving quick filtering is an important contribution due to the database size. Including geography in filters is important due to rapidly escalating attention to geographic factors in public health. The implementation of mechanisms for iterative place-time-concept filtering makes it possible to narrow searches efficiently and quickly from thousands of documents to a small subset that meet place-time-concept constraints. Support for a more-like-this query creates the potential to identify unexpected connections across diverse areas of research. Multi-view visualization methods support understanding of the place, time, and concept components of document collections and enable comparison of filtered query results to the full set of publications. Introduction Commercial search engines, along with related search methods integrated into information repositories such as PubMed, have revolutionized information retrieval; but, for many real-world challenges they solve only part of the problem. Place and time are fundamentally important to many health science and policy tasks and current search strategies are only just beginning to take them into account. Further, the goal of information retrieval is usu- ally to support some knowledge building or application tasks. Knowledge is often derived by uncovering and con- textualizing relations among place, time, and concepts. The research reported here addresses the challenges of finding relevant information in document repositories and supporting its use through strategies for efficient retrieval, filtering, and contextualization. Visual analytics strategies are introduced that (a) provide quick geo- graphic, temporal, and concept overviews for relatively large initial query results to PubMed (e.g., the 5591 docu- ments retrieved with the query H5N1 OR "avian influ- * Correspondence: maceachren@psu.edu 1 GeoVISTA Center, Department of Geography, The Pennsylvania State University, University Park, PA, USA Full list of author information is available at the end of the article