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Clinical Trial Information

What is a clinical trial?

Why are clinical trials important?

What are the benefits and risks of participating in clinical trials?

What is randomisation?

What is a placebo?

What is double blinding?

What is a protocol?

What is informed consent?

Can I leave a clinical trial after it has begun?

Who funds or sponsors clinical trials?

Who manages clinical trials?

What if a participant experiences side effects while participating in a clinical trial?

What is the data and safety monitoring board and how does it ensure participant safety?

Why might a clinical trial be stopped early?

Who monitors the conduct of protocols?

Will my health information remain confidential and private?

What is the role of an ethics committee in a clinical trial?


What is a clinical trial?                                                                                                      ct image med

Clinical trials are medical research studies used to compare two or more treatments (often a treatment vs a placebo). They are typically set up to determine which of the two treatments is safer and more effective .

A clinical trial is typically conducted by dividing a group of participants into two groups, one of which is given the medication and the other group is given a placebo. A process of ‘randomisation’ is used to determine who is assigned to each group (see below).

After entry to the trial each participant is followed up in an identical fashion to allow the researchers to measure the results of each treatment.

Why are clinical trials important?

Clinical trials provide the most convincing evidence about the safety and efficacy of a medication. Clinical trials are regarded as essential for this purpose.

Clinical trials are important because they are virtually the only way to identify an effect of treatment amongst the large amount of variability occurring in both the nature of their illness and their response to a treatment.

This variation makes it difficult to measure the effect of a treatment. If any single individual is given a treatment and appears to recover it is typically impossible to be certain that the treatment was responsible for the improvement. Clinical trials use large population numbers, and randomisation techniques, to assist in eliminating confounding variables.

What are the benefits and risks of participating in clinical trials?

Potential benefits:

  • You will make a valuable contribution to medical research
  • You may benefit from receiving the intervention if it is effective
  • You will be monitored closely for any side effects
  • You will obtain additional medical care
  • You will be take an active role in your health

Potential risks:

  • You may experience adverse effects
  • The intervention may not be effective and therefore you may receive no benefit
  • You may need to have more doctor visits than normal

What is randomisation?

Randomisation is process in which participants are randomly allocated to one of two (or more) treatment groups within a clinical trial. It ensures that the groups are as similar as possible apart from the trial treatment. This means that any differences in the results between the groups can be attributed to the different treatments rather than to differences in the characteristics of the participants in the groups.

What is a placebo?

A placebo is a treatment that has no actual health effect but looks identical to the treatment being studied. In a clinical trial we compare results between the placebo group and treatment group to determine the efficacy of the medical treatment in question.

What is double blinding?

A double blind study is one in which neither the participants, nor the clinical trial staff, are aware of which treatment the participants receive until after the study is completed. Double blinding helps to prevent bias in data collection and reporting, meaning that any pre-conceived ideas the researchers or participants may have about the effect of the treatment cannot influence the study results.

What is a protocol?

A protocol is a document that sets out the details of the clinical trial and the methods to be followed. It includes information about the background and aims of the trial, the procedures for recruitment of participants and assessment of patient events, details about the interventions being investigated, the possible risks and benefits of the intervention, and data analysis. The protocol also specifies how the researchers will monitor and manage adverse patient events.

What is informed consent?

Informed consent is a process that involves all clinical trial participants. Before deciding whether or not to take part, all potential participants are given written information about the trial aims, duration, requirements of taking part, and the potential risks and benefits. During the informed consent process, potential participants can also ask the research team about anything that is not clear to them, and they may discuss it with their own doctor or family before they decide.

The aim of informed consent is to ensure that potential participants can make a fully informed decision about participating. Participants must sign a written consent document (Participant Information and Consent Form) before joining a trial. This means that they understand what participating in the trial will involve, and they agree to take part.

Can I leave a clinical trial after it has begun?

Participation in the trial is voluntary and you may choose to withdraw at any time. Withdrawal from a trial will not change the relationship between a participant and their doctor.

Who funds or sponsors clinical trials?

Clinical trials may be funded by numerous organisations such as government granting bodies (eg. NHMRC, NIH), charities (eg. National Heart Foundation, Arthritis Foundation), pharmaceutical companies, universities and research institutions, and philanthropic organisations.

Who manages clinical trials?

Clinical trials are managed by large teams of scientists and doctors who work in universities and hospitals. All clinical trials have a Principal Investigator who oversees the trial. Trial coordinators, data managers, statisticians, nurses and other health care professionals also play a part in running clinical trials.

What if a participant experiences side effects while participating in a clinical trial?

If a participant experiences illness or possible side-effects while in the trial they should seek advice from their usual doctor.

What is the data and safety monitoring board and how does it ensure participant safety?

The data and safety monitoring board (DSMB) is a group of doctors, statisticians and researchers who meet regularly to review the progress of a clinical trial. These people are experts in the conduct of clinical trials but are independent of the organisations that are managing the clinical trial for which they are DSMB members. Their role is to monitor the safety of participants and the quality of the data.

Why might a clinical trial be stopped early?

There are a number of reasons why a clinical trial may be stopped early, these may include:

  • If participants experience unanticipated and serious side effects
  • If evidence shows that the risks are outweighed by the benefits.
  • If evidence has shown that the intervention being tested is effective
  • If it is not possible to recruit enough participants
  • If results from other trials that answer the same research question become available

Who monitors the conduct of protocols?

There are several groups of people that monitor the conduct of a clinical trial including clinical monitors, auditors (such as TGA or trial sponsors) and the ethics committee which approved the clinical trial.

Will my health information remain confidential and private?

The individual data collected for each participant will only be accessible to the researchers analysing the results of the trial. Identifying information will be removed before analysis begins. Results for individual participants are confidential and are not made available or reported. Furthermore, it is not possible to identify individual participants through the published results.

What is the role of an ethics committee in a clinical trial?

An ethics committee is an independent group of people who ensure that research is conducted according to the guidelines on Good Clinical Practice and the ethical principles of the Declaration of Helsinki. Ethics committees are comprised of medical researchers, health professionals, lay people, lawyers and pastoral care workers. In Australia, all clinical trials must be approved by an ethics committee before they begin to recruit participants.

What happens when a clinical trial is over?

The results of any clinical trial are carefully analysed and reported in a number of ways including publication in the scientific and medical literature, presentation at conferences, and incorporation into guidelines for clinical practice.

After a trial is completed, the researchers will make the results available to any participants who have indicated that they would like to know the trial outcomes.