European Journal of Epidemiology

, Volume 27, Issue 10, pp 823–825 | Cite as

Meta-analyses: with confidence or prediction intervals?

  • Arnaud ChioleroEmail author
  • Valérie Santschi
  • Bernard Burnand
  • Robert W. Platt
  • Gilles Paradis
Letter to the Editor

In meta-analyses, when data are pooled and analyzed using random effect models, it is standard to report a confidence interval (CI) around the effect estimate [1, 2, 3], as reported in several meta-analyses published in the European Journal of Epidemiology [4, 5, 6]. Nevertheless, when heterogeneity is substantial, some authors have proposed to report a prediction interval (PI) rather than a CI to have a better appreciation of the uncertainty around the effect estimate [7, 8, 9].

What is the meaning of confidence and prediction intervals? Using results from a meta-analysis demonstrating the impact of pharmacist interventions on blood pressure [10], we explain how to use each of these intervals.

In a recent systematic review with meta-analyses of randomized controlled trials, we showed that pharmacist interventions improve the management of major cardiovascular disease risk factors in outpatients, including hypertension, dyslipidemia, and smoking [10]. Interventions were led by the...


Blood Pressure Confidence Interval Diastolic Blood Pressure Usual Care Effect Estimate 
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.


Conflict of interest

There are no conflicts of interest and no specific source of funding.


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Copyright information

© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  • Arnaud Chiolero
    • 1
    • 2
    Email author
  • Valérie Santschi
    • 1
    • 2
  • Bernard Burnand
    • 1
    • 3
  • Robert W. Platt
    • 2
  • Gilles Paradis
    • 2
  1. 1.Institute of Social and Preventive Medicine (IUMSP)Lausanne University HospitalLausanneSwitzerland
  2. 2.Department of Epidemiology, Biostatistics and Occupational HealthMcGill UniversityMontrealCanada
  3. 3.Swiss CochraneLausanneSwitzerland

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