B – Use of double dummy trial

Marušić A, Ferenčić SF. Adoption of the double dummy trial design to reduce observer bias in testing treatments. Journal of the Royal Society of Medicine 2013;106(5):196-198
(doi: 10.1177/0141076813485350)

The use of the double dummy trial was reported to reduce observer bias. Although the use of placebo controls (dummy treatments) and blind assessment to decrease observer bias in clinical trials was introduced at the end of the 19th century, it was not until the second half of the 20th century, that placebo controls became more widely used. The preparation of the placebo interventions becomes more complicated: to control for both delivery methods, the trial needs to have adequate control groups for both treatments – an approach referred to as the ‘double dummy’ trial design.http://www.ncbi.nlm.nih.gov/pubmed/23761529