Although geographical information systems offer many benefits, they can be a challenge to navigate. As Web designers have long known, involving users in the process of a resource’s development is crucial to maximizing its usefulness. Catherine Burroughs notes in Measuring the Difference: Guide to Planning and Evaluating Health Information Outreach
, “Direct user feedback is preferred when trying to establish a basic understanding about problems, satisfaction, and unmet information access needs ….”28
To enhance TOXMAP’s usability and keep its presentation readable and understandable, TEHIP has performed a variety of usability studies, including conducting intermittent, informal usability tests on various versions of TOXMAP, requesting feedback from specific users (such as health professionals), and reviewing feedback from user e-mails. In addition, the National Library of Medicine conducted two professionally moderated Web-based focus groups on TOXMAP in April 2005, which provided detailed usability comments.
In general, a focus group consists of specially selected individuals brought together to discuss and share opinions about a specific issue. Its primary goal is to “gather data on the opinions, knowledge, perceptions, and concerns of small groups of individuals ….”29
“The power of focus groups lies in the fact that they are nondirective. Information can surface that otherwise might not emerge in a structured interview.”30
The two TOXMAP focus groups consisted of professionals and concerned citizens (9 to 12 individuals per group), with a balance of adult men and women. The participants were employed in the environmental, occupational, industrial, and public health and information fields, and reported being active in community or national efforts related to environmental health. Prior to the 60-minute discussions, each spent 20 to 30 minutes completing a Web-based “tour” of TOXMAP’s current and potential future features, along with several simple exercises. Both the tour and the exercises were developed specifically for these sessions.
A Web-based interaction system31
was used to conduct the discussions in an effort to maximize time efficiency and cost effectiveness for participants (no travel time/cost), to provide a comfortable approach for users familiar with the Web environment, and to build rapport and the potential for developing future working relationships. This approach also enabled the participants to observe particular parts of the Web site as a group (displayed and controlled by a moderator), and allowed for simultaneous discussion and comments. The proceedings became a written transcript from which further analysis was conducted.
Feedback on TOXMAP was generally positive across both groups. Some of the “best-liked” characteristics of TOXMAP included its “drill-down” to detailed information, quick links to relevant information, and its ease of navigation and searchability. TOXMAP’s chemical search feature received the highest rating. Respondents found TOXMAP to be appropriately designed for anyone in the health profession, including researchers, academics, students, and activists.
Some of the weaknesses of the site noted by participants included the “small” maps, which were sometimes difficult to read; somewhat “cluttered” screens; lack of a glossary of acronyms and terms; and inability for the user to limit the trend data to a specific time frame.
Participants provided opinions on possible improvements to the TOXMAP interface and functionality, and regarding addition of specific types of new data to overlay with the existing TRI data, such as health statistics, additional census data, school locations, and environmental data (e.g., superfund sites, water quality, pesticide usage, and floodplains).
Based largely on user feedback, NLM recently added Superfund sites and contaminants to TOXMAP and is also planning other features such as more data sets (additional epidemiological data related to cancer, heart disease, and asthma); the ability to display multiple chemicals on a single map; updated and expanded U.S. Census demographics; and the ability to select whether to display one or a combination of types of releases (air, water, land, and/or underground injection).