“Why can’t I just take my Electronic Health Record (EHR) charts and move them from one system to another one? This seemingly-simple question has vexed builders of a national Health IT infrastructure, and leaves us with the dissatisfying answer of “it’s not that easy.”
Every EHR system uses a different internal way of collecting and organizing its medical data – so simply exporting a series of tables (either as spreadsheets or csv files) won’t work, except for a few areas – like patient demographics and other summary data.”
Article
Robert Rowley, EHR Bloggers, 27 May 2010

