While undergoing any clinical trials two main type of experiments used are single blind and double blind. Selection of right trial is important as it can affect the outcome of the experiment.So the selection of right trial is important otherwise there would be errors.
In single blind study the subjects don’t know whether they are subject of experiment or control group members. But the tester knows but subject does not know its identity.
In double blind study both the subject and tester does not know their identity and roles, both are not told their identity in the experiment.
According to me the double blind study is more better as it prevents the bias in the experiments and results. It is used to prevent bias due to demand characteristics.