Nationwide management of laboratory
information with the NPU terminology
Ulla Magdal, MI
National Board of Health, Denmark
What the NPU terminology is
 Coding system for identification of medical
laboratory results
 Developed jointly by IFCC and IUPAC via the
 (Sub)Committee on Nomenclature for Properties and Units
IFCC – International Federation of Clinical Chemistry and
Laboratory Medicine
 IUPAC - International Union of Pure and Applied Chemistry

 In nationwide use in Denmark and Sweden
Who I am and what I do
Manager of the Danish version of the
NPU terminology for the Board of
Health
 Titular member for IFCC of the
international ’NPU committee’

Laboratory technologist – clinical
biochemistry
 Degree in Health Informatics


Work on
laboratory informatics
 concept analysis
 translation of SNOMED CT

Ulla Magdal Petersen
Denmark
ump@sst.dk
Why a terminology for laboratory results?
ensure that examination results are
 fully defined in the clinical context
 transferable between systems
 comparable to others of same kind
 reuseable – for decision support, calculations,
research, statistics
For this you need
 (common IDs)
 clear and stable definitions of result types
Describe the property examined

Use structured definitions - describing
what part of the universe you are observing
 what component you observe in that part
 what property of that component you estimate

(add SI unit and more detail where relevant)

Use standard scientific concepts and terms
Patient—Body; mass = ? kilogram
Blood—Erythrocytes; volume fraction = ?
Blood—Hemoglobin(Fe); substance concentration = ? millimole
per litre
Translation of structured NPU definitions



Keep the structure as a carrier of meaning
Translate each term of the definition
Assume that the translated definition describes the same concept
System
term
Component
term
Kind of property
term
Unit
term
NPU03431
Urine—Sodium ion; substance concentration = ? millimole per litre
Urine—Ion sodium; concentration en matière = ? millimole/litre
Urin—Natrium-ion; stofkoncentration = ? millimol per liter
Health care in Denmark
 The National Health




Service serves all 5,5
mill. citizens
27 hospitals owned by
5 Regions (no major
private hospitals)
15 600 hospital beds
3600 general
practitioners have 90%
of all patient contacts
GPs are largely publicly
funded
NPU in Denmark






1998 – 2001 Danish Board of Health supports
development of the NPU coding system and of its Danish
version
2001 NPU coding system recommended for national use in
Denmark. Most biochemistry labs implement it
2003 Biochemistry labs with EDI - 95 % NPU coded
2006 20 million NPU coded results from labs to GPs
2007 Web applications for GPs to order and access results
from labs nationwide – NPU is main coding system
2009 NPU use slowly spreading into immunology,
microbiology and genetics. A few local and proprietary
coding systems remain in use
The Danish NPU Release Center
 2 specialists (with a laboratory and informatics
background)
 translate the NPU terminology into Danish
 manage and publish the Danish NPU version via a




national website
publish a Users’ Guide
support and advise users (laboratories and system
developers)
manage a (small) non-standard extension for specific
Danish use
analyse ’coding needs’ of Danish users for
communication to the international NPU committee
EHR in Danish health care 2009
About 35% of hospital beds
are served by Electronic
Health Records (EHR), usually
combined with direct access
to local lab systems (LIS)
 All general practitioners use
EHR - about 20 different
systems!
 All GP’s receive laboratory
data messages directly into
the EHR

MedCom - the Danish Health Data Network

Co-operative venture between authorities, organisations
and private firms linked to the Danish healthcare sector

Nationwide transmission of messages between GPs and
hospitals and health authorities

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



discharge reports
referrals
laboratory requests
laboratory reports
drug prescriptions
reimbursement
www.medcom.dk
Messages to/from GPs (1992 – 2008)
MedCom -The Danish Health Data Network
Messages/Month
1500000
1400000
1300000
1200000
1100000
1000000
900000
800000
700000
600000
500000
400000
300000
200000
100000
0
Prescriptions
1039105 = 84%
1389023
73%
Disch. Letters
1131750
94%
%
682923 ==85
Lab. reports
543040 = 99
988151
82 %
Lab Requests
349840 = 85 %
Referrals
177525 = 65 %
92
93
94
95
96
97
98
99
20
O1
O2
O3
Source: www.medcom.dk July 2009
O4
O5
O6
O7
O8
Reimbursement
21049 = 99 %
Web based ordering of laboratory tests
 on-line laboratory requesting from GP to
laboratory of choice
Web based access to laboratory information
GP may search for laboratories that hold recent results for
a certain patient
 look up the results right away

- dependant on proper permissions, secure software and digital signature!
It was not that easy – some challenges
 Conceptual - a new medical language
 using standard terminology and SI units
 naming the information produced, not the process
 describing properties of the patient, not of the sample
 Technical
 long names vs. screen sizes and field lengths
 primitive information models
 Organizational and cultural
 distrust of ’codes and numbers’ in parts of the medical
environment
 it-setback caused by a total makeover of public
administration in 2007
Tradition for naming results ’by process’
50 years ago
Red cell microscopy
was a good name for
Blood—Erythrocytes, number concentration
– but the process has changed
Definitions by ’patient property estimated’ last longer
 And are clinically more relevant

But they make unwieldy names, especially on screens
 Local names and and abbreviations are often used
 NPU information can be available ’behind the screen’

Tradition for naming results ’by process’
50 years ago
Red cell microscopy
was a good name for
– but the process has changed
NPU01960 Blood—Erythrocytes;
number concentration
1012/litre
Definitions by ’patient property estimated’ last longer
 And are clinically more relevant

But they make unwieldy names, especially on screens
 Local names and and abbreviations are often used
 NPU information can be available ’behind the screen’

Complexity of lab data is underestimated




Clinical, administrative and technical data often needed
Not ’slots’ in systems or messages
There is always a ’test code’ slot
But there are no NPU definitions with ’extra info’


Local ’test codes’ replace NPU codes in order to convey
e.g.:





New, more sensitive method
POCT result
Patient is in pregnancy care program
Bill the sports clinic for this
The information models need revision
If you only have a
hammer, all your
problems must be nails
Harmonization is a long process
The Danish release center
 does almost all the initial coding work for ’first
time’ laboratories
 publishes a national ’User’s Guide’
 sends out a monthly NPU newsletter
 regularly offers all regions to send in their coding
tables for checking and updating
 helps create Danish ’shortcut names’ for use in
EHR result overviews
Visible gains
 Reusable information in EHRs
 calculation of clinical indexes
 graphical representation of results
9
8,5
8
7,5
Serie1
7
6,5
6
1
2
3
4
5
6
7
 Security when transmitting lab results nationwide
 result values end up in the right row every time
 A national reference
 laboratories gradually achieve a common language
 NPU codes are used in laboratory documentation, e.g. in
certification or accreditation processes
Useful links

Short description of the terminology - with links
http://www.sst.dk/English/NPULaboratoryTerminology.aspx

Latest version of the NPU terminology for download
(abbreviated definitions, .csv files)
http://www.labterm.dk/Enterprise%20Portal/NPU_download.aspx

All the background litterature
http://old.iupac.org/divisions/VII/labinfo/English/IFCC_Document
s.html
Please ask questions