“The idea has been that these HIEs would knit different ambulatory practices together, giving physicians using disparate Electronic Health Records systems a common place to exchange clinical data with each other – at first, it would simply be the summary data (problem lists, medication lists, allergies, immunizations, and lab results) that could be encoded in standard-format transport files (CCDs or CCRs). More robust full-document exchange of complete chart notes, imaging files, etc., would come later.
Besides connecting community docs together, these HIEs were also to be places where different large institutions could connect – hospitals and academic centers could exchange information with each other. More importantly, these HIEs were places where community doctors could connect with their local hospital(s), as well as with clinical laboratories.”
Article
Robert Rowley, EHR Bloggers, 26 January 2012

