Sham comparator is an inactive therapy made to look identical to the active therapy.
SHAM COMPARATOR ARM:
A group of participants that receives a procedure or device that is made to be indistinguishable from the actual procedure or device being studied but does not contain active processes or components. An arm or group in which only a mock therapy that is not a drug is administered. In trials of devices or procedures, however, the placebo control is often a sham intervention that differs only minimally from the active or effective procedure and that may expose subjects to a degree of risk similar to that of the active procedure.
Sham controls in clinical trials of devices and procedures are used
- Either to conﬁrm or refute the results of open-label trials
- Circumstances in which outcomes that are partially or entirely subjective are primary.
However, while the use of sham controls is likely to provide the highest quality and potentially most generalizable clinical trial data, the use of a sham control must be carefully contemplated in light of its appropriateness and feasibility and applied within a formalized ethical framework. Only through a careful assessment of the risks to research subjects of being exposed to a sham control and of the knowledge that will be gained through direct comparison of a placebo to active device or procedure can investigators decide whether the use of a sham control versus a usual care control is most advantageous.