Clinical trials are certain types of trials conducted by health institutions in order to collect different efficacy and safety data, concerning various different types of therapy protocols, devices, diagnostics, drugs and other. When the authorities approve the satisfactory information gathered from non-clinical safety, clinical trials may take place. These trials involve patients or healthy volunteers in small, initial pilot studies. When these are over, larger scale studies can take place. In these larger studies, patients are often able to compare their currently prescribed treatment with the new products which are the subject of the study. Most clinical trials involve sizable costs, so that is why all the services and people involved get paid by sponsors. Sponsors usually include biotechnology companies, pharmaceutical companies and governmental organizations. It is not uncommon for a clinical trial to be managed by units in the academic sectors or contract research organizations. It is also very common for clinical trials to include patients who suffer from various specific medical conditions but cannot be healed by using conventional methods of treatment. Early phases of clinical trials involve healthy volunteers who are motivated by financial incentives. The subjects usually need to stay on site at the unit for no more than 30 nights, but sometimes even longer. Once the device or medication gets identified, pilot experiments take place so that the designing of the clinical trial may take place. Elderly people are often excluded from clinical trials because they tend to be affected by health issues much more frequently and they do not provide reliable data. It is also important to decide what to compare the new device or medicament with and what patients could benefit from it the most.
Clinical trials are designed to provide the scientists with valuable information. The trials may be very efficient in comparing the effectiveness in patients with specific diseases and common interventions for those diseases, assessing the effectiveness and safety of the new device or medication compared to standard devices or medications, assessing the effectiveness and safety of already marketed medications or devices for new indications, assessing the effectiveness and safety of different doses of medications, and so on.
Clinical trials can also be classified by the way the researches included in the study actually behave. Different types of clinical studies include compassionate use trials, quality of life trials, treatment trials, diagnostic trials, screening trials, prevention trials, interventional studies and observational studies.