Masking

**Semantic type:** Activity

**Definition:** The mechanism used to obscure the distinctive characteristics of the study intervention or procedure to make it indistinguishable from the comparator. NOTE: Blinding refers to study participants while masking refers to the study intervention. [After Crisp A. Blinding in pharmaceutical clinical trials: An overview of points to consider. Contemp Clin Trials. 2015;43:155-163.] See also blinding.

**Synonyms:** - masking - masking (study treatment)