In many studies, some participants receive the new drug, and other participants receive a placebo. A placebo looks just like the drug, but is an inactive substance. A double blind clinical study is when neither researcher nor participant knows who is getting placebo and who is getting the drug. A single blind study is when participants do not know whether they are getting placebo or drug, but the study team does know.
Study participants who receive either standard procedure for the illness or placebo (no medicine) as compared to study participants who are receiving a new drug, medical device, procedure, or prevention.
If researchers show that a drug has 'efficacy' (or is 'efficacious'), they show that it improves a disease or condition in a controlled environment, like a laboratory. Proving efficacy is a first step to show that the drug can work when it is taken in the right way. If researchers show that a drug is 'effective', they show that it improves a disease or condition outside of a controlled environment. For instance, if a drug lowers cholesterol in a study, it is efficacious. But if that drug has to be taken exactly 1 hour after eating, it might not be effective because it is too hard for people to remember to take it at exactly the right time.
Study participants who receive the new drug, device, procedure, or prevention that is being researched. This group is often compared to a 'control group', which does not receive the new drug, device, procedure, or prevention.
A participant's written agreement (signed and dated) to be in a clinical study after fully discussing complete and important information about the clinical study with the researchers (investigator and study coordinator):
A registered nurse (RN) with advanced educational or clinical training. Nurse Practitioners are licensed by the state and authorized to perform many types of care previously only available from doctors. For instance, in many states, Nurse Practitioners can prescribe medications.
A person seeking medical care. Participants in clinical studies are not called 'patients', because they may not be receiving medical care. For instance, they may be receiving a new drug that has not yet been proven to work, or they may be receiving a placebo.
A placebo looks like a drug, but is actually an inactive substance that is not expected to have any effect on your health. Sometimes a placebo is called a 'dummy pill' or 'sugar pill'. Old placebos were often true 'sugar pills', but modern placebos usually do not contain sugar. A research study may also use a placebo for a medical device or procedure. For instance, a placebo device could look like the real device, but not actually function.