title: Exploiting the potential of large databases of electronic health records for research using rapid search algorithms and an intuitive query interface.
abstract: OBJECTIVE
  UK primary care databases, which contain diagnostic, demographic and prescribing information for millions of patients geographically representative of the UK, represent a significant resource for health services and clinical research. They can be used to identify patients with a specified disease or condition (phenotyping) and to investigate patterns of diagnosis and symptoms. Currently, extracting such information manually is time-consuming and requires considerable expertise. In order to exploit more fully the potential of these large and complex databases, our interdisciplinary team developed generic methods allowing access to different types of user.
  
  
  METHODS
  Using the Clinical Practice Research Datalink database, we have developed an online user-focused system (TrialViz), which enables users interactively to select suitable medical general practices based on two criteria: suitability of the patient base for the intended study (phenotyping) and measures of data quality.
  
  
  RESULTS
  An end-to-end system, underpinned by an innovative search algorithm, allows the user to extract information in near real-time via an intuitive query interface and to explore this information using interactive visualization tools. A usability evaluation of this system produced positive results.
  
  
  CONCLUSIONS
  We present the challenges and results in the development of TrialViz and our plans for its extension for wider applications of clinical research.
  
  
  CONCLUSIONS
  Our fast search algorithms and simple query algorithms represent a significant advance for users of clinical research databases.
authors.affiliation: Department of Informatics, University of Sussex, Brighton, UK.
authors.forename: A Rosemary
authors.initials: AR
authors.lastname: Tate
authors.forename: Natalia
authors.initials: N
authors.lastname: Beloff
authors.forename: Balques
authors.initials: B
authors.lastname: Al-Radwan
authors.forename: Joss
authors.initials: J
authors.lastname: Wickson
authors.forename: Shivani
authors.initials: S
authors.lastname: Puri
authors.forename: Timothy
authors.initials: T
authors.lastname: Williams
authors.forename: Tjeerd
authors.initials: T
authors.lastname: Van Staa
authors.forename: Adrian
authors.initials: A
authors.lastname: Bleach
mesh_terms: D000465:Algorithms; D016208:Databases, Factual; D057286:Electronic Health Records; D006801:Humans; D016247:Information Storage and Retrieval / Q000379:methods*; D009862:Online Systems; D018579:Patient Selection; D011786:Quality Control; D016032:Randomized Controlled Trials as Topic; D006113:United Kingdom; D014584:User-Computer Interface
keywords: Data quality; Data visualisation; Electronic Health records; Primary Care