What are the strengths and weaknesses of the randomised control trial study design?
This question would best be answered by listing the relative merits and drawbacks of the
study design, with elaboration on the subjects of treatment allocation, randomisation to
eliminate selection bias, the need for adequate sample size to achieve power and a discussion
of the logistics of conducting multi-centre trials. Additional marks were awarded for
discussion of blinding, prospective design, “efficacy versus effectiveness” trials, applicability
and ethical considerations. The need for “equipoise” as a pre-requisite for randomisation in a
clinical trial was not discussed by candidates. Definition of Type I and Type II errors and the
relative merits of this study design in avoiding these errors required more detailed discussion.
Syllabus EBM 2.b, d, e;
Referrence: Statistical Methods for Anaesthesia and Intensive Care (Chapter 4), Myles and
Unlike the college answer to Question 6 from the first paper of 2014, the commentary here is actually useful to the revisiing candidate. Particularly helpful is the text reference. That chapter from Myles and Gin is still not as good as the LITFL page on randomised controlled trials, which offers an excellent breakdown of what would be relevant to a good detailed answer.
Advantages of randomised control trial study design:
|Disadvantages of randomised control trial study design
Statistical methods for anaesthesia and intensive care (P S Myles, T Gin - 1st ed - Oxford : Butterworth-Heinemann, 2001)
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