High speed clinical data retrieval system with event time sequence feature: With 10 years of clinical data of Hamamatsu University Hospital CPOE

Objectives: This paper illustrates a high speed clinical data retrieving system, from 10 years of data of operating hospital information system for the purposes of research, evidence creation, patient safety, etc., even incorporating time sequence of casual relations. Methods: Total of 73,709,298 records of 10 years at Hamamatsu University Hospital (as of June 2008) are sent from HIS retrieval system in HL7 v2.5 format. Hierarchial variable length database is used to install them. Results: A search for "listing patients who were prescribed Pravastatin (Mevalotin and generic drugs, any titer)" took 1.92 seconds. " Pravastatin (any) prescribed and recorded AST > 150 within two weeks" took 112.22 seconds. Searching conditions can be set to be more complex, connected by Boolean operator and/or. This system called D*D is in operation at Hamamatsu University Hospital since August 2002. It is used for 48,518 times (monthly average of 703 searches). Neither searching, nor background export of data from HIS caused delay of routine operating CPOE. Conclusions: Search database outside of routine operating CPOE, with daily export of order data in HL7 v2.5 format, is proved to provide excellent search environment without causing trouble. Hierarchial representation gives high-speed search response, especially with time sequence of events.