title: Manual semantic tagging to improve access to information in narrative electronic medical records.
abstract: OBJECTIVE
  To assess effectiveness of information retrieval from narrative patient records utilizing manually supplied semantic tags.
  
  
  METHODS
  Retrospective evaluation of narrative electronic record notes with respect to consistency of manually supplied semantic tags. Assessment of retrieval effectiveness using string matching methods and methods based on structural characteristics of data.
  
  
  METHODS
  Department of Neurology in a Norwegian university hospital using a document based electronic patient record system offering template assisted manual semantic indexing of textual record notes.
  
  
  METHODS
  Proportion of consistently tagged information. Retrieval effectiveness expressed as recall (sensitivity) and precision (positive predictive value).
  
  
  RESULTS
  Seventy-five percent of the content was consistently tagged. Retrieval models based on simple string matching performed better than models based on semantic tags alone with respect to best mean recall and mean precision at high recall-levels. Models combining both simple string matching and semantic tagging performed better than separate models with respect to best mean recall (0.95) and mean precision at high levels of recall.
  
  
  CONCLUSIONS
  Although template assisted semantic indexing of narrative electronic patient record notes showed suboptimal consistency, it significantly improved retrieval effectiveness with respect to best mean recall obtained by individual strategies and with respect to precision at any recall level.
authors.affiliation: Department of Clinical Neurosciences, The Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Gustav
authors.initials: G
authors.lastname: Mikkelsen
authors.forename: Jan
authors.initials: J
authors.lastname: Aasly
mesh_terms: D000043:Abstracting and Indexing; D006801:Humans; D016247:Information Storage and Retrieval; D016347:Medical Records Systems, Computerized / Q000592:standards*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012660:Semantics; D012680:Sensitivity and Specificity