1. Senior Technical Manager
Close Encounters of the Structured Kind - HL7 in the NHS - Anthony Mottram
11 December 2003
Close Encounters
of the Structured Kind
HL7 in the NHS
Anthony Mottram
Senior Technical Manager

2. History of structured messaging in the National Health Service
– ADI (Application Data Interchange)
Required specific end to end software definitions
Low level coding – usually in C
Very unreliable
Dependent upon communication protocol
Supplier driven

3. History of structured messaging in the National Health Service
– Northern Flat File Development
Precursor to CMDS – episodic data from mainframe PAS
Flat file format – dubious data content
Helped to identify numerous errors in data integrity
Dependent upon communication protocol
Supplier driven

4. History of structured messaging in the National Health Service
1994 – ASTM1238
Developed at John Radcliffe Hospital, Oxford
Intended specifically for clinical results
First move towards producing a structured message for the NHS
Independent of communication protocol
Supplier driven

5. History of structured messaging in the National Health Service
1994 – EDIFACT
International standard for numerous purposes
UK structure defined & controlled by the NHS
First used for CDS but extended to clinical messaging
Early use of the VGP segment allowed too much freedom
Independent of communication protocol, but tied to X.400

6. History of structured messaging in the National Health Service
200? – HL7 version 3
International standard specifically for healthcare organisations
Defined & controlled by the NHS & HL7 UK
Intended for all health-orientated messaging
Previous versions already in use world-wide
Actively being defined and developed
Independent of communication protocol

7. What’s wrong with the messages we already use?
Communication errors have fatal consequences
Patients die
Unambiguous communication is essential
Hip replacement – which one? – there are two
John Smith – which one? – there are thousands
Local dialects lead to misunderstanding
Full blood count? – number of tests – lab-dependent
Amoxycillin? – strength - dosage

8. Why HL7? HL7 is a world-wide health-orientated message structure
Contribution from international expertise in healthcare
Operates as an approved standards authority
Delivers open standards

9. Why HL7 version 3? Previous versions relied on end-to-end agreement
Versatile structure provides for changing needs
Uses the latest technology
Human and machine readable in the same structure
Accommodates local anomalies in a national format
Removes ambiguity – prevents errors
Effective in-built message and communications tracking

10. Conclusion Focused entirely on the need of the Health Service
Versatile enough to cover all aspects of healthcare
Total commitment from suppliers and healthcare professionals

11. Someday all messages will be like this
And we will all understand each other.
It’s good to talk HL7v3