18. A system for processing a personal health record (PHR) including a plurality of events each having a time stamp, the system comprising: a mapper for creating a plurality of event-concept pairs by mapping each event of the plurality of events in the PHR to a corresponding health concept among a plurality of health concepts, for assigning to each of the plurality of event-concept pairs the time stamp of the event of that event-concept pair, and for identifying associations among the plurality of event-concept pairs, wherein the plurality of health concepts are categorized into a plurality of categories, wherein identifying associations involves referencing a database of stored information specifying associations between health concepts among the plurality of health concepts, wherein at least some of the specified associations are between health concepts that are in different categories in the plurality of categories, and wherein the plurality of categories are medical tests, diseases, symptoms, medications, and treatments; and a threader for identifying an associative subset of event-concept pairs among the plurality of event-concept pairs, wherein the associative subset includes those events in the PHR that are either associated with a header concept or are associated with another event within the associative subset and wherein the associated subset includes health concepts that are in different categories of the plurality of categories, and for linking a plurality of members of the associative subset of event-concept pairs to form a thread, wherein the thread presents a relationship among the plurality of members of the associative subset of event-concept pairs, and wherein the mapper and the threader are implemented in hardware.
20. The system of claim 18 , wherein the mapper identifies associations among the plurality of event-concept pairs by referencing a database that stores a plurality of health concepts and a plurality of associations among the plurality of health concepts.