Measuring dissimilarity in online health search activities.

There is growing evidence of the use of the Internet to obtain critical health information as well as increased diversity of user groups. While users of web-based information often report their reliance on healthcare providers for validation of information, it has yet to be determined if this is universally true across all types of information or user groups. In some cases consumers may aggregate in places where they trust web information (relative to provider-based information), such as areas of unsettled diagnostic methods or ambiguous treatment protocols. To date little research has been done to identify and differentiate clusters of health consumers and their similarities related to type of information sought. Data from a study of consumer Web search activity in a post-intervention era serves as a natural experiment, and can identify whether clusters of "digitally underserved groups" persist in the US, following national efforts to eliminate barriers to health information access. This exploratory technology assessment study seeks to differentiate and delineate specific information behaviors, across targeted healthcare subgroups. Doing so allows the design of more effective strategies to promote the use of the Web as a health education and health promotion tool, under the envisioned shared decisionmaking, consumer-centric health information model, critical to the proposed US national health information infrastructure.