What is the purpose of employing a double-blind study design?

The purpose of employing a double-blind study design is to reduce bias by keeping both participants and experimenters unaware of treatment assignments. This design is critical in research, particularly in clinical trials, as it helps ensure that neither group can influence the outcomes based on their expectations or beliefs about the treatment. When participants are unaware of whether they are receiving the experimental treatment or a placebo, it helps mitigate any placebo effect, while also preventing experimenters from unintentionally influencing participants' responses or behaviors through their reactions or expectations. This rigour in maintaining objectivity strengthens the validity of the study's findings and allows for more reliable conclusions to be drawn about the effects of the treatment being tested.