Introduction to Clinical Trials in Practice

Question 1

What mnemonic can be used to characterise RCTs?

Answer 1

CRABS (Control, Randomisation, Allocation, Blinding, Sufficient sample size)

Question 2

Outline the concept of equipoise

Answer 2

Equipoise is the ethical principle that in research involving assigning patients to different treatment arms, the participants (e.g. clinicians, patients) should have no evidence-based reason to prefer any one arm over the others. Community equipoise refers to the situation where there is no agreement within a community of ‘experts’ that one treatment is superior to another. The concept of equipoise is related to ‘uncertainty’, and equipoise can be seen as representing the point (or distribution) of maximum uncertainty.

Question 3

In what situation may it be difficult to ensure potential trial participants are well informed and provide consent?

Answer 3

There are many such situations including, for example:

Trials involving young children, or ‘incapacitated’ adults such as those with low levels of understanding, or patients following severe trauma. Usually informed consent is requested from a proxy

Emergency situations in which there is no time to seek consent (when decisions may have to be made by treating clinicians, with the agreement of an independent ethics committee – see below)

People with low literacy levels (when information will need to be provided in a non-written form)

People with low levels of the language in which the trial is being conducted (when information will need to be provided in a translated form)

Question 4

What are the main rationales behind the regulations governing the good practice? (2)

Answer 4

To safeguard patients

To provide credible data