Snomed CT: A richer and more reliable source of clinical data for primary care

The Snomed CT medical terminology system provides more comprehensive and reliable data on diseases, diagnoses and treatments for primary care than is currently available with the classification models currently in use, according to a new thesis from Karolinska Institutet. The data provided is important for being able to monitor more effectively the health status of patients and the population, to make comparisons and conduct research.

In a new doctoral thesis from Karolinska Institutet, researchers have examined diagnoses and treatments in primary care using Snomed CT (Systematized nomenclature of medicine, clinical terms), the worlds largest terminology system. Their results reveal the emergence of a new clinical reality. Of the 2.5 million-plus diagnoses processed from patient records they found, for example, that infectious diseases and problems in the gastrointestinal tract are much more common than is understood from the statistics provided by conventional terminology systems. Snomed CT also captures data on inflammatory diseases and pain, data that is otherwise unavailable. The thesis also shows that Snomed CT provides more detailed information on treatments and other clinical measures, such as drug use and advice.

"Snomed CT seems to find hidden data and process it so that it can be viewed from different perspectives," says Anna Vikström at the Department of Neurobiology, Care, Sciences and Society at Karolinska Institutet and the Centre for Family and Community Medicine. "It provides more reliable and more secure information of use to primary care personnel, patients, researchers and decision-makers."

Anna Vikström says that current classification models, despite being a golden standard, often have an outdated, narrow structure.

"Stomach cancer is classified only as a cancer. Snomed CT, on the other hand, also classifies it as a disease of the gastrointestinal tract," she says.

Another example is vascular dementia, which is classified as a mental disease in conventional systems; in Snomed CT, however, it is also searchable as a disease of the nervous system and as an injury.

But when will Swedish primary care be ready to switch to this kind of common international database of medical terminology? According to Anna Vikström, many people in and outside Sweden believe that using Snomed CT is the right way to go, although the idea is not for it to serve as a single terminology resource but as an integrated part of the patient records system.

"We need a uniform terminology system to do follow-ups and make comparisons, to monitor the state of health of patients and the population at large, and to conduct research, she adds. Today there are few systems that can make the data uniform so that it can be documented and communicated over time between organisations and across national boundaries."

Thesis

Terminology systems for health problems and procedures in primary care
Anna Vikström
September 2011, ISBN: 978-91-7457-461-6