A single-blind study is a clinical trial or research design where the participants do not know to which group they have been assigned (e.g. the treatment group or the control group), but the researchers do.
The main purpose of blinding participants in a single-blind study is to reduce the bias that might arise from participants’ expectations, beliefs or behaviours. For example, participants who know they are receiving a treatment might report better outcomes due to the placebo effect, or they might behave differently compared to those who know they are in the control group.