ABSTRACT
A laboratory experiment takes place in laboratory where experimental manipulation is facilitated. A clinical study takes place in the settings of clinical medicine. Experimental studies in medicine that involve humans are called clinical trials because their purpose is to draw conclusions about a particular procedure or treatment. There are experimental errors that include all types of extraneous variation due to intrinsic variability of experimental material, lack of uniformity in the methodology of conducting the experiment, and lack of representation of the sample to the population. Therapeutic trials are the test of remedies on a disease or a disorder that is followed whenever some improved technique is reported. Such tests of treatment methods differ little from the regular clinical procedures. Uncontrolled trials are studies in which the investigators experiment with the experimental drug, but the treatment is not compared with another treatment, at least not formally.
