Clinical Trials
WHAT IS A CLINICAL TRIAL?
A clinical trial is research using human participants that is intended to advance medical knowledge.
Participants receive specific interventions according to the research plan or protocol created by the investigators. These interventions may be medical products, such as drugs or devices; new or revised medical practices; or changes to participants' behavior, such as diet. Clinical trials may compare a new medical approach to a standard one that is already available, to a placebo that contains no active ingredients, or to no intervention. Some clinical trials compare interventions that are already available to each other.
Clinical trials used in drug development are sometimes described by phase.
WHO CONDUCTS CLINICAL TRIALS?
Every clinical study is led by a principal investigator, who is often a medical doctor. Clinical studies also have a research team that may include doctors, nurses, social workers, and other health care professionals.
Clinical studies can be sponsored, or funded, by pharmaceutical companies, academic medical centres, voluntary groups, or federal or provincial levels of government.
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Clinical studies have standards outlining who can participate. These standards are called eligibility criteria and are listed in the protocol.
Some research studies seek participants who have the illnesses or conditions that will be studied, other studies are looking for healthy participants, and some studies are limited to a predetermined group of people who are asked by researchers to enroll.
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The factors that allow someone to participate in a clinical study are called inclusion criteria, and the factors that disqualify someone from participating are called exclusion criteria. They are based on characteristics such as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions.
WHO CAN PARTICIPATE IN A CLINICAL STUDY?
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Participating in a clinical study contributes to medical knowledge. The results of these studies can make a difference in the care of future patients by providing information about the benefits and risks of therapeutic, preventative, or diagnostic products or interventions.
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Clinical trials provide the basis for the development and marketing of new drugs, biological products, and medical devices. Sometimes, the safety and the effectiveness of the experimental approach or use may not be fully known at the time of the trial.
Some trials may provide participants with the prospect of receiving direct medical benefits, while others do not. Most trials involve some risk of harm or injury to the participant, although it may not be greater than the risks related to routine medical care or disease progression.
Many trials require participants to undergo additional procedures, tests, and assessments based on the study protocol. These requirements will be described in the informed consent document. A potential participant should also discuss these issues with members of the research team and with his or her usual health care provider.
CONSIDERATIONS FOR PARTICIPATION IN A CLINICAL STUDY
Source: U.S. National Library of Medicine