Manual semantic tagging to improve access to information in narrative electronic medical records.
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.
Mikkelsen
Gustav
G
Department of Clinical Neurosciences, The Norwegian University of Science and Technology, Trondheim, Norway.
Aasly
Jan
J
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