Every day, research uncovers new information about diseases and their treatment. Clinical research studies are an important step in making new medications available for future use. Here are a few definitions of Clinical Trial:
What is a clinical trial?
Although there are many definitions of clinical trials, they are generally considered to be biomedical or health-related research studies in human beings that follow a pre-defined protocol. ClinicalTrials.gov includes both interventional and observational types of studies. Interventional studies are those in which the research subjects are assigned by the investigator to a treatment or other intervention, and their outcomes are measured. Observational studies are those in which individuals are observed and their outcomes are measured by the investigators. – from http://clinicaltrials.gov/ct2/info/understand