The U.S. Agency for Healthcare Research and Quality has created a public website to disseminate critical information regarding its health information technology initiative. The website is maintained by AHRQ's Natiomal Resource Center (NRC) for Health Information Technology. In the latest continuous quality improvement project, the NRC used the site's search logs to extract user-generated search phrases. The phrases were then compared to the site's controlled vocabulary with respect to language, grammar, and search precision. Results of the comparison demonstrate that search log data can be a cost-effective way to improve controlled vocabularies as well as information retrieval. User-entered search phrases were found to also share many similarities with folksonomy tags.