What is a blind trial ?
A blind trial is a trial where the people taking part do not know which treatment they are receiving.
They may receive the new treatment or the standard treatment, depending on the trial design. All patients receive identical injections or tablets so they cannot know which treatment trey are receiving.
The trial is single blinded; when the patient dose not know. The study is double blinded when both patient and his doctor do not know if the patient receives the referent or experimental treatment.
This approach helps researchers to avoid bias (Bias occurs when human choices or other factors unrelated to the treatment under investigation change a study’s results).