The comparative study on concept representation between the UMLS and the clinical terms in Korean medical records

Summary

Objective:

The National Library of Medicine's Unified Medical Language System (UMLS) is a rich source of knowledge in the biomedical domain. The UMLS is used for research and development across wide range of different applications. In this paper, we evaluated the coverage of UMLS as compared with medical terms extracted from Korean medical records and identified differences in concept representation between two terminology sets.

Design and measurement:

We measured the concept coverage of the UMLS. For this study, we mapped the clinical terms extracted from the discharge records of Seoul National University Hospital (SNUH) to the UMLS.

Results:

Thirty-five percent of the entry terms used in chief complaint of SNUH were conceptually matched with the UMLS ‘Sign or Symptom’ concepts. Fifty-eight percent of the terms were found to be matched with the UMLS ‘Disease or Syndrome’ concept rather than the ‘Sign or Symptom’ concept. The remaining 7% were not found in the UMLS concepts. We then analyzed some of different expression patterns used by the two term sets and addressed issues to be taken into consideration.

Conclusion:

We found out that the UMLS was comparable with Korean medical records, since most of concepts of Korean medical records were covered with the UMLS concepts.

Introduction

The emergence of electronic medical record (EMR) requires a new recognition of clinical terminologies and nomenclatures. Increasingly, consistent entry of information, comparable across care providers and care settings are being emphasized. To achieve this, the developers and implementers of EMR recognize that clinical information should be expressed using comprehensive and well-structured terminologies [1]. EMR requires standard vocabularies to ensure the consistent representation of data. These standard vocabularies need to cover diverse and enriched fields of medical content, thereby facilitating semantic information retrieval, clinical decision support and efficient care delivery [2], [3]. Several medical terminology systems such as Unified Medical Language System (UMLS) [4], SNOMED [5] and GALEN [6] have been developed for this purpose. Of these systems, we examined the potential of the Unified Medical Language System Metathesaurus^® (UMLS MT) of National Library of Medicine. The UMLS MT is used in many applications including information retrieval from databases with human-assigned subject index terms and from free-text information sources; linking patient records to related information in bibliographic, full-text or factual databases; natural language processing and automated indexing research, and for structured data entry. To obtain coherent, comparable results in data creation applications, like patient data entry, it is necessary to define which UMLS MT concepts and terms should be included in the records being created [7].

Nowadays, information sharing between different information systems becomes a buzzword. The information sharing means semantic interoperability rather than system interoperability. The primary requirement for the semantic information sharing is the well-established terminology. Having sound terminology for EMR will benefit wide range of clinical applications and various clinical researches based on the EMR.

The goal of this study is to evaluate the pertinence and usability of the UMLS. We examined the potential of UMLS for the reference terminology of Korean medical records especially for the future EMR. In this paper, we present the procedures of concept mapping and the results. In addition, we describe the different expression patterns of the two terminology sets.