blind study

A blind study (or blinded experiment) is a scientific test in which information about the experiment—such as which participants are receiving a treatment versus a placebo—is withheld from the participants, the researchers, or both until the trial is complete. The term aims to describe a methodology designed to minimize confirmation bias and the placebo effect. The usage dates back to the late 19th and early 20th centuries, relying on the metaphor of physical blindness to represent a lack of specific knowledge or awareness.

While the term remains standard in many scientific communities due to its historical prevalence and clear technical definition, it has faced criticism from disability advocacy groups and inclusive language guides. Critics argue that using "blind" as a metaphor for "unaware," "ignorant," or "lacking insight" perpetuates ableist stereotypes that equate vision impairment with a lack of understanding. Conversely, proponents of the term argue that it is a neutral, established term of art in statistics and medicine without malicious intent. In response to these concerns, some organizations, such as the American Psychological Association (APA), have suggested using terms like "masked" to avoid ableist metaphors.

Example:
"To ensure the results were not influenced by the placebo effect, the researchers conducted a double-blind study."

Example:
"The journal now encourages authors to use 'masked review' rather than 'blind review' to describe their peer-review process."