This question may seem basic, but there are many layers to it. The interviewer is testing your actual knowledge of clinical research, and they are also checking to see how easily you can explain a complicated concept.
"Clinical research encompasses a large range of human health studies that test medical treatments, vaccines, prescription drugs, and medical devices for example. Clinical research ensures that these methods and medications are safe and effective before they are introduced to the public.It is a highly evidence-based science."
Entry Level answer example
"To me, I have found that clinical research is best described as a branch of healthcare dedicated to safety standards of medication and other medical products meant for human consumption."
Experienced answer example
"From a technical perspective, clinical research relates to medical research, particularly clinical trials. For me, it is an important part of the healthcare industry that allows us to determine new forms of treatment and ultimately, save lives with future discoveries."