AP PSYCHOLOGY

Detailed explanation-1: -A type of clinical trial in which neither the participants nor the researcher knows which treatment or intervention participants are receiving until the clinical trial is over. This makes results of the study less likely to be biased.

Detailed explanation-2: -A double-blind study is one in which neither the participants nor the experimenters know who is receiving a particular treatment. This procedure is utilized to prevent bias in research results. Double-blind studies are particularly useful for preventing bias due to demand characteristics or the placebo effect.

Detailed explanation-3: -In a single-blind study, patients do not know which study group they are in (for example whether they are taking the experimental drug or a placebo). In a double-blind study, neither the patients nor the researchers/doctors know which study group the patients are in.

Detailed explanation-4: -In a double-blind study, both participants and experimenters are blinded. In a triple-blind study, the assignment is hidden not only from participants and experimenters, but also from the researchers analyzing the data.

Detailed explanation-5: -Therefore, both research participants and researchers are blind to this information. Double-blind studies help in reducing the biases like the placebo effect, experimenter bias, and experimenter expectancy effect that hinder the results and conclusions of the study.