Evaluating interfaces for government metasearch

Metasearch tools, which combine search results from any number of independent search engines, could be useful in a range of tasks and especially for integrating information from separate government agencies. However, it is not immediately clear what user interfaces might be appropriate for presenting results from more than one source. We evaluated four interface designs with real tasks from Centrelink, Australia's social services agency, and with a working metasearch tool. Test users recorded similar overall effectiveness across these interfaces, but did not like the most familiar options, a single ranked list or a link to broaden search scope. Interfaces which supported identifying, understanding, and selecting between sources were strongly preferred.