On Framing the Research Question and Choosing the Appropriate Research Design

  • Patrick ParfreyEmail author
  • Pietro Ravani
Part of the Methods in Molecular Biology™ book series (MIMB, volume 473)


Clinical epidemiology is the science of human disease investigation with a focus on diagnosis, prognosis, and treatment. The generation of a reasonable question requires the definition of patients, interventions, controls, and outcomes. The goal of research design is to minimize error, ensure adequate samples, measure input and output variables appropriately, consider external and internal validities, limit bias, and address clinical as well as statistical relevance. The hierarchy of evidence for clinical decision making places randomized controlled trials (RCT) or systematic review of good quality RCTs at the top of the evidence pyramid. Prognostic and etiologic questions are best addressed with longitudinal cohort studies.

Key words

Clinical epidemiology methodology research design evidence-based medicine randomized controlled trials longitudinal studies 


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Health Sciences CentreNewfoundlandCanada
  2. 2. Staff Nephrologist , Divisione di NeprologiaAzienda InstitutiCremonaItaly

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