Triple-blind (i.e., triple-masking) studies are randomized experiments in which the treatment or intervention is unknown to (a) the research participant, (b) the individual(s) who administer the treatment or intervention, and (c) the individual(s) who assess the outcomes. The terms blind and masking are synonymous; both terms describe methods that heslp to ensure that individuals do not know which treatment or intervention is being administered. The purpose of triple-blinding procedures is to reduce assessment bias and to increase the accuracy and objectivity of clinical outcomes.
Conducting a triple-blind study is difficult. The following two examples highlight some challenges in conducting and evaluating triple-blind studies.
The first example, from a study by Abraham Heller and colleagues, highlights the difficulties in conducting a triple-blind study in a clinical setting ...