title: Annotation Analysis for Testing Drug Safety Signals using Unstructured Clinical Notes.
abstract: BACKGROUND
  The electronic surveillance for adverse drug events is largely based upon the analysis of coded data from reporting systems. Yet, the vast majority of electronic health data lies embedded within the free text of clinical notes and is not gathered into centralized repositories. With the increasing access to large volumes of electronic medical data-in particular the clinical notes-it may be possible to computationally encode and to test drug safety signals in an active manner.
  
  
  RESULTS
  We describe the application of simple annotation tools on clinical text and the mining of the resulting annotations to compute the risk of getting a myocardial infarction for patients with rheumatoid arthritis that take Vioxx. Our analysis clearly reveals elevated risks for myocardial infarction in rheumatoid arthritis patients taking Vioxx (odds ratio 2.06) before 2005.
  
  
  CONCLUSIONS
  Our results show that it is possible to apply annotation analysis methods for testing hypotheses about drug safety using electronic medical records.
authors.affiliation: Stanford Center for Biomedical Informatics Research, Stanford University, USA. plependu@stanford.edu.
authors.forename: Paea
authors.initials: P
authors.lastname: Lependu
authors.forename: Srinivasan V
authors.initials: SV
authors.lastname: Iyer
authors.forename: Cédrick
authors.initials: C
authors.lastname: Fairon
authors.forename: Nigam H
authors.initials: NH
authors.lastname: Shah