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Plan and Conduct of Research: Observational and Interventional Study Designs

  • Vikram Kate
  • Sathasivam Sureshkumar
  • Mohsina Subair
Chapter

Abstract

  • The study design is the overall strategy chosen to logically assimilate the different study components so as to effectively address the research question and is determined by the research question and not vice-versa.

  • Study designs in medical research can be broadly classified as basic, observational and interventional studies. Observational studies can be further divided into descriptive and analytic studies.

  • Case-control study proceeds from outcome to exposure, whereas cohort study proceeds from exposure to outcome.

  • RCTs can be divided as parallel arm, cross-over and factorial studies based on design and as superiority and non-inferiority based on hypothesis.

  • The keystones in the decision making process for suitable study design is “reducing bias” and “increasing efficiency”.

  • Although RCTs and controlled cohort studies provide higher level of evidence, the best study design is the one that answers the research question most explicitly.

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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Vikram Kate
    • 1
  • Sathasivam Sureshkumar
    • 2
  • Mohsina Subair
    • 3
  1. 1.Department of Surgery and Senior Consultant General and Gastrointestinal SurgeonJawaharlal Institute of Postgraduate Medical Education and ResearchPondicherryIndia
  2. 2.Department of SurgeryJawaharlal Institute of Postgraduate Medical Education and ResearchPondicherryIndia
  3. 3.Department of Plastic and Reconstructive SurgeryPostgraduate Institute Medical Education and ResearchChandigarhIndia

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