An Introduction to HL7 Version 2 Charlie Bishop 9 February 2005 HL7 and its key role in NPfIT and Existing Systems Integration

Agenda History of v2 Scope of v2 Structure of the v2 Standard v2 Message Structure v2 Issues The Future

Version 2.0 HL72UK vA.2 Version 2.6 – under development / ballot Version 2.1 Version 2.2 Version 2.3 Version Version 2.4 Version 2.5 History of v2 Version Version 3 – development starts HL7 UK established

An International Standard USA (90% of hospitals) UK Canada Australia Netherlands Germany Japan Others

Scope Patient Administration –Registration / MPI –ADT / Inpatients –Scheduling / Outpatients –Waiting List (UK) –Medical Records Clinical –Orders –Results –Provision of Care Financial

Structure of the Standard Chapter 1. Introduction 2. Control 3. Patient Administration 4. Order Entry 5. Query 6. Finance 7. Observation Reporting 8. Master Files 9. Medical Records 10. Scheduling 11. Patient Referral 12. Patient Care 13. Clinical Laboratory Automation 14. Network Protocols

Message Structure Triggers Messages –Segments Fields Data Types

Example v2 Message MSH|^~\&|LAB|767543|ADT|767543| ||ADT^A04|XX3657|P|2.4 EVN|| |||| PID||| ||EXAMPLE^DAVID^S|| |M|||23 MAINSTREET^^ANYTOWN^ > ^AN10 8SW|| PD1||||DR A WELBY PV1||0||NEW|||DR K JONES

XML Representation Provides compatibility with industry standard tools Alternative syntax –Data semantic is identical Simple transform between 2 syntaxes –Segments, Fields and Data Types represented as elements

Example v2 XML Message | ^~\& LAB ADT ADT A04...

Delimited vs. XML MSH|^~\&|LAB|767543|ADT|767543| ||ADT^A04|XX3657|P|2.4 EVN|| |||| PID||| ||EXAMPLE^DAVID^S|| |M|||23 MAINSTREET^^ANYTOWN^^AN10 8SW|| PD1||||DR A WELBY PV1||0||NEW|||DR K JONES | ^~\& LAB ADT ADT A04 XX3657 P NHS NH AB12345 EXAMPLE DAVID S M 23 MAIN STREET ANYTOWN AN10 8SW DR A WELBY 0 NEW DR K JONES

Issues Inconsistent use –Multiple versions –Z-Segments –Interpretation –Localisation Support for clinical data Communication approach –Broadcast vs. targeted Seen one HL7 v2 interface– seen one HL7 v2 interface

The Future HL7 v2 will continue to be developed HL7 v2 will continue to be widely used in the NHS Delimited vs. XML Mapping to v3 HL7 UK v2 sub-group

Thank you!