taught by this reference
collecting data from a plurality of sources comprising drug information, adverse effects relating to drugs and patient information; placing collected data into a data structure, wherein data from sources not already in a relational database structure are parsed into a relational database structure; generating a relational database for relating drug information, adverse effects and patient information; assembling said patient information, drug information and adverse effects into individual cases, wherein each said case contains patient information, information related to a drug administered to that patient and a description of an adverse drug reaction;
The reference teaches collecting and parsing patient information, drug information, and adverse drug reactions from multiple sources into individual cases in a relational database, which corresponds to extracting electronic clinical data associated with historical healthcare encounters for a plurality of patients.