I understand that in a single blind study the investigator knows what is being used on the subject and that can cause a bias but in the double blind study who knows what is being given to the patients? That might be an easy question but I am still confused as to who would know what is being given to who. For example if you have the pill you want to test and the placebo pill who would know which patient got which pill if both the investigator and the patient both do not know.But besides this question I can see why a double blind study is more accurate. The experiment results will be better if there is less bias. It is always good to make sure the patient does not know what they are taking so they do not change the results depending on what they feel. I also believe that the patients should also not have a bias so that should be determined before the experiment. This can help the results be more accurate.