title: Comparison of validity of mapping between drug indications and ICD-10. Direct and indirect terminology based approaches.
abstract: BACKGROUND
  Mapping of drug indications to ICD-10 was undertaken in Korea by a public and a private institution for their own purposes. A different mapping approach was used by each institution, which presented a good opportunity to compare the validity of the two approaches.
  
  
  OBJECTIVE
  This study was undertaken to compare the validity of a direct mapping approach and an indirect terminology based mapping approach of drug indications against the gold standard drawn from the results of the two mapping processes.
  
  
  METHODS
  Three hundred and seventy-five cardiovascular reference drugs were selected from all listed cardiovascular drugs for the study. In the direct approach, two experienced nurse coders mapped the free text indications directly to ICD-10. In the indirect terminology based approach, the indications were extracted and coded in the Korean Standard Terminology of Medicine. These terminology coded indications were then manually mapped to ICD-10. The results of the two approaches were compared to the gold standard. A kappa statistic was calculated to see the compatibility of both mapping approaches. Recall, precision and F1 score of each mapping approach were calculated and analyzed using a paired t-test.
  
  
  RESULTS
  The mean number of indications for the study drugs was 5.42. The mean number of ICD-10 codes that matched in direct approach was 46.32 and that of indirect terminology based approach was 56.94. The agreement of the mapping results between the two approaches were poor (kappa = 0.19). The indirect terminology based approach showed higher recall (86.78%) than direct approach (p < 0.001). However, there was no difference in precision and F1 score between the two approaches.
  
  
  CONCLUSIONS
  Considering no differences in the F1 scores, both approaches may be used in practice for mapping drug indications to ICD-10. However, in terms of consistency, time and manpower, better results are expected from the indirect terminology based approach.
authors.forename: Y
authors.initials: Y
authors.lastname: Choi
authors.forename: C
authors.initials: C
authors.lastname: Jung
authors.forename: Y
authors.initials: Y
authors.lastname: Chae
authors.forename: M
authors.initials: M
authors.lastname: Kang
authors.forename: J
authors.initials: J
authors.lastname: Kim
authors.forename: K
authors.initials: K
authors.lastname: Joung
authors.forename: J
authors.initials: J
authors.lastname: Lim
authors.forename: S
authors.initials: S
authors.lastname: Cho
authors.forename: S
authors.initials: S
authors.lastname: Sung
authors.forename: E
authors.initials: E
authors.lastname: Lee
authors.affiliation: Sukil Kim, The Catholic University of Korea, College of Medicine, 505 Banpo-Dong, 137-701 Seoul, Republic of Korea, E-mail: sikimmd@gmail.com.
authors.forename: S
authors.initials: S
authors.lastname: Kim
mesh_terms: D002317:Cardiovascular Agents / Q000009:adverse effects* / Q000145:classification / Q000627:therapeutic use*; D059019:Clinical Coding; D019992:Databases as Topic; D006801:Humans; D038801:International Classification of Diseases; D008432:Mathematical Computing; D008492:Medical Informatics Computing; D015203:Reproducibility of Results; D009626:Terminology as Topic
chemical_list: D002317:Cardiovascular Agents
keywords: Drug indication database; International Classification of Diseases (ICD); semantic mapping