Definition of Clinical Research Terms

To help you understand clinical research, the following are definitions of some of the jargons and phrases commonly used.

A
Arm	Any of the treatment groups in a randomised trial.
Adverse event	An unexpected medical problem that happens during treatment with a drug or other therapy. Adverse effects do not have to be caused by the drug or therapy, and they may be mild, moderate, or severe.

B
Biomarker	A biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease. It may be used to see how well the body responds to a treatment for a disease or condition.
Blind (and double-blind)	A blind study is a type of study in which the patients (single-blind) or the patients, the doctors and the people who analyse the results (double-blind) do not know the specific type of treatment the patient receives until after the clinical trial is over. The opposite of a blind study is an open label study. A blind study is a type of study in which the patients (single-blind) or the patients, the doctors and the people who analyse the results (double-blind) do not know the specific type of treatment the patient receives until after the clinical trial is over. The opposite of a blind study is an open label study.

C
Cohort	In medicine, a cohort is a group that is part of a clinical research study and is observed over a period of time.
Control group	A group of study subjects, identified before a study begins, which comprises participants who do not have the disease, or get the intervention, procedure or whatever is being studied, but in all other respects are as nearly identical to the test group as possible.

D
Double-blind	See definition for "Blind".

E
Eligibility criteria or exclusion / inclusion criteria	In clinical research, eligibility criteria refer to requirements that must be met for an individual to be included in a study. These requirements help make sure that participants in a study are as similar to each other as possible in terms of age, type and stage of disease, general health, and previous treatment. When all participants meet the same eligibility criteria, it gives researchers greater confidence that results of the study are caused by the intervention being tested and not by other factors.
Epidemiology	The study of the patterns, causes, and control of disease in groups of people.

I
Informed consent	In clinical research, informed consent is a process during which a person is given important facts about a study before deciding whether or not to participate. It also includes informing the patient when there is new information that may affect his or her decision to continue. Informed consent includes information about the possible risks, benefits, and limits of the research study.
Institutional Review Board (IRB)	A group of scientists, doctors, clergy, and lay people that review and approve the action plan for every clinical research study involving human subjects or tissues. There is an IRB at every healthcare facility that conducts clinical research. IRBs are designed to protect the people who take part in a clinical research. They check to see that the trial is well designed, legal, ethical, does not involve unnecessary risks and includes safeguards for patients.
Intervention / Interventional / Non-interventional	In medicine, intervention refers to a treatment or action taken to prevent or treat disease, or improve health in other ways. An interventional research study refers to a clinical research that involves intervention. Also known as clinical trials.
Investigator	A researcher in a clinical research study. The person who leads the study is known as the lead investigator or principal investigator.

O
Observational studies	A type of study where individuals are observed or certain outcomes are measured. No attempt is made to affect the outcome (for example, no treatment is given).
Outcome	A specific result or effect that can be measured. Examples of outcomes include decreased pain, reduced tumour size, and improvement of disease.

P
Placebo / Placebo-controlled	A placebo is an inactive substance or treatment that looks the same as, and is given the same way as, an active drug or treatment being tested. The effects of the active drug or treatment are compared to the effects of the placebo. Placebos are administered to avoid false reporting of results due to the perception of participants and investigators. A placebo-controlled study refers to one in which the control group receives a placebo.
Protocol	A detailed plan of a scientific or medical experiment, treatment, or procedure. In clinical research, it states what the study will do, how it will be done, and why it is being done. It explains how many people will be in the study, who is eligible to take part in it, what study drugs or other interventions will be given, what tests will be done and how often, and what information will be collected.

Randomisation

Randomisation refers to the allocation to groups by chance, like throwing a dice. In clinical research, participants are assigned by chance to separate groups that compare different treatments or other interventions. Randomisation gives each participant an equal chance of being assigned to any of the groups.

A randomised clinical research is a study in which the participants are assigned by chance to separate groups that compare different treatments; neither the researchers nor the participants can choose which group. Using chance to assign people to groups means that the groups will be similar and that the treatments they receive can be compared objectively. At the time of the trial, it is not known which treatment is best. It is the patient's choice to be in a randomised trial.

T
Therapy	Treatment

Definition of Clinical Research Terms

Prof Ivy Ng

SingHealth GCEO