Drug Safety

, Volume 33, Issue 7, pp 559–567 | Cite as

Enhancing Pharmacosurveillance with Systematic Collection of Treatment Indication in Electronic Prescribing

A Validation Study in Canada
  • Tewodros Eguale
  • Nancy Winslade
  • James A. Hanley
  • David L. Buckeridge
  • Robyn Tamblyn
Short Communication


Background: Adverse drug reaction reports used in pharmacosurveillance often lack complete information on treatment indication that is important for benefit-risk analyses and clinical and regulatory decision making. A systematic documentation of treatment indication using electronic prescribing applications provides an opportunity to develop new pharmacosurveillance tools that will allow evaluation of drugs by weighing benefits and risks for specific indications, and evaluate off-label prescribing. In addition, interfacing indications with reminders and clinical guidelines can enhance clinical decision making. We investigated the validity of treatment indications documented using an electronic prescribing system at the time of prescribing.

Objectives: To determine the sensitivity and positive predictive value (PPV) of an electronic prescribing system in documenting treatment indications at the time of drug prescribing, and to investigate the use of treatment indication data to evaluate off-label prescribing in primary-care practice.

Study Design and Setting: We prospectively assessed the validity of documenting treatment indication using an electronic prescribing system by comparing it with treatment indications documented by physician-facilitated medical chart review (‘gold standard’). Sensitivity and PPV were evaluated in 338 patients of 22 community-based primary-care physicians in Quebec, Canada, in 2006.

Results: The sensitivity of the electronic prescribing system in documenting treatment indication was 98.5% (95% CI 96.5, 99.5) and the PPV of the system in accurately identifying the treatment indication was 97.0% (95% CI 94.2, 98.6). The treatment indication data collected using this system allowed assessment of off-label prescribing.

Conclusions: The electronic prescribing system offers a valid method for documenting treatment indication at the time of prescribing. Our results provide strong evidence to support incorporating mandatory recording of treatment indication in integrated electronic prescribing systems to provide a critical piece of information for the evaluation of safety and effectiveness of drugs.


Positive Predictive Value Treatment Indication Electronic Prescribe Correct Indication Electronic Prescribe System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This study was carried out by the Clinical and Health Informatics Research Group, Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada.

The study was funded by Ministère de la Santé et des Services Sociaux (MSSS), Québec. Tewodros Eguale is supported by The Canadian Institutes of Health Research (CIHR) Frederick Banting and Charles Best Canada Graduate Scholarship. David Buckeridge is supported by a Canada Research Chair in Public Health Informatics. Robyn Tamblyn, Nancy Winslade and James Hanley have no conflicts of interest to declare.


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Copyright information

© Adis Data Information BV 2010

Authors and Affiliations

  • Tewodros Eguale
    • 1
  • Nancy Winslade
    • 1
  • James A. Hanley
    • 1
    • 2
    • 3
  • David L. Buckeridge
    • 1
    • 2
  • Robyn Tamblyn
    • 1
    • 2
  1. 1.Department of Epidemiology, Biostatistics, and Occupational HealthMcGill UniversityMontrealCanada
  2. 2.Department of MedicineMcGill UniversityMontrealCanada
  3. 3.Department of Mathematics and StatisticsMcGill UniversityMontrealCanada

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