ICPC-2 Plus takes SNOMED for a test drive
The developers of the ICPC-2 PLUS general practice terminology have completed a test set of common general practice terms that has been mapped from the terminology to SNOMED CT AU for testing by software vendors in the Wave 2 sites for the implementation of the PCEHR.
The Family Medicine Research Centre (FMRC) at the University of Sydney, which developed and maintains the ICPC-2 Plus terminology used in a number of GP desktop software packages, has worked with NEHTA and the RACGP to create the test set of 100 general practice terms.
SNOMED has been chosen as the terminology for problem diagnosis codes in the PCEHR but it is not used in any of the GP desktop electronic health records. ICPC-2 Plus is used in about eight products used in Australian general practice, although the two vendors with the largest market share, Medical Director and Best Practice, use their own coding system.
Graeme Miller, medical director of the FMRC, said the map from the selected ICPC-2 Plus terms to SNOMED CT AU will be distributed to software vendors to test the functionality of the GP desktop medical records to transfer SNOMED codes to the PCEHR.
Dr Miller said the 100 terms were only a very limited data set and are not fit for purpose for clinical use. However, they are the start of a wider project to map all 8000 ICPC-2 Plus codes to SNOMED, which he hopes will be available next year.
“A lot of clinical coding is quite opaque to GPs, but basically ICPC-2 Plus is a controlled terminology,” Dr Miller said. “That means it's a terminology that is in a specific set of terms, in this case a set of terms that is mapped to the International Classification of Primary Care (ICPC).
“ICPC Plus was developed by the Family Medicine Research Centre for use in both the BEACH data collection program and in GP EHRs and we've been supplying it through vendors to GPs for some considerable time. It has about 8000 terms in it which are derived from the terms that GPs actually use to label patient problems.”
The codes are what sits behind the pick-lists that GPs use in their EHRs to label the patient's problem. Keywords are provided to bring up the pick-list such as “OA” for osteoarthritis, which then brings up a list such as osteoarthritis of the knee or osteoarthritis of the hip.
GPs can also use ICPC-2 for recalls or auditing purposes to bring together groups of patients with the same diagnosis. It is also used for research purposes and in the eCollaboratives program, which helps GPs to improve the quality of their clinical data.
The government chose SNOMED as the standard for problem diagnosis labels, but as it is not yet used in any GP clinical software it will need to mapped to terminologies that are used, such as ICP-2 Plus and the bespoke terminologies used in Medical Director and Best Practice.
The RACGP chose 100 commonly used general practice problem diagnosis labels, which has now been mapped to ICPC-2 Plus and to SNOMED, Dr Miller said.
“There are only 100 of these out of the 8000 that GPs around the country use, so it is not fit for purpose. All it is intended for is to provide a test for the software adaptions the vendors are putting in order to export problem lists from the GP's record to the PCEHR.
“We are going to distribute it to the vendors for them to use it for testing and we can then see how that works.”
Dr Miller said the FMRC is also working on a parallel exercise to develop an international SNOMED general practice reference set, which is a cut-down version that can be used as the front end for GPs using SNOMED.
“What we've done is collate term sets like ICPC-Plus from several different countries, map them all to SNOMED and then condense them down into a conjoint international set. That will be complete probably by the end of August. We are then going to map that to ICPC as well.
“Ultimately, that reference set, which again will be about 8000 to 10,000 terms, will then possibly be used in GP desktop systems and replace ICPC-2 Plus but also the terminology sets in Medical Director and Best Practice, if they agree to it.”
For the time being, GPs will be able to upload documents to the PCEHR either as texts coded in ICPC-Plus or in the MD or Best Practice codes, he said. “But they won't be standardised – they'll be there essentially as just terms. It will be a while before anyone is uploading SNOMED.
“We've been in the business of trying to build these systems for about 20 years and we've learned to be very patient. It takes a long time. It is also a problem that the data systems within the current GP desktop programs are all different – there are about 10 systems out there, all of which record data in different fields in different ways with different data field names and different coding systems. There is a lot of variance to get rid of. All of that is going to take time to sort out.”
He said the centre was exploring funding options to create a full map for the SNOMED reference set. This funding will need to be ongoing as once the map is built, it will require regular maintenance.
“You've got to continuously maintain terminologies, because medical language changes over time and you have to adapt to that. It's not just diseases that change, but labelling changes. What was emphysema became chronic obstructive airways disease and then became chronic obstructive pulmonary disorder. The names change even though the problems remain the same. You've got to adapt the terminology to what is called the linguistic drift.”
Posted in Australian eHealth