What is a completely randomized design?

A completely randomized design is an experimental setup where subjects are randomly assigned to different treatment groups without any restrictions or considerations for other factors. This approach ensures that each participant has an equal chance of being assigned to any group, minimizing bias and variability. It is often used in experiments to test the effects of treatments in a straightforward manner, allowing for clear comparisons between groups. However, it may not account for confounding variables that could affect the outcome.