Clinical trials


Clinical trials explained

Page last updated: January 2025

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Clinical trials can help show whether a new approach to prevention, screening, diagnosis, or treatment works better than current methods and is safe.

People volunteer in clinical trials to help test how well the new way works and if it causes side effects or other problems.  

If the new way is shown to work better than the existing method, it may become available. Some clinical trials compare existing approaches to see which one is more effective.

Search for clinical trials

Understand clinical trials in your language

Learn about the role and value of clinical trials through a series of multilingual videos produced by the  Australian Clinical Trials Alliance.

The videos are available in Arabic, Chinese ( simplified and traditional), Filipino, Greek, Hindi, Italian, Punjabi, Spanish and Vietnamese. Written versions of the videos are also available.

More resources in other languages

Cancer research overview

Cancer research has led to the medical treatments and health programs available today. These advances have improved outcomes for people with all types of cancer over the past 20 years, with increases in both length of survival and quality of life.

The search for better ways to prevent, diagnose and treat cancer is ongoing. There are three main types of cancer research:

  • population research – researchers known as epidemiologists look for patterns and trends to work out how and why cancers occur in groups of people (populations).
  • laboratory research – scientists do experiments with the building blocks of disease, such as cells and blood, to try to understand how cancer works, and they also study and develop new drugs and treatments in the laboratory.
  • clinical research – research is done on people to better diagnose, prevent and treat cancer, often in a hospital or treatment centre.

Population research and laboratory research are often the starting point for clinical research, which may involve clinical trials.

"I had to fill out a questionnaire about my emotional and physical wellbeing on the day of the trial and the following day. This gave me something to do and I felt that I was actively participating in my own health care" Marg

Cycle of research

The research process is a continuous cycle. People affected by cancer mainly take part in clinical trials, a type of clinical research. Research can lead to new and improved therapies becoming part of standard care.

  • Population research identifies trend or problem (e.g. disease, risk factor)
  • Laboratory research investigates a problem, develops a possible solution, and tests how well it works (in test tubes) and if it seems safe (in animals)
  • Clinical research tests the solution (e.g. a new drug, treatment, program) on people
  • New therapy may be approved for use on people if proven safe, effective and as good as or better than existing treatments; longterm benefits and risks will be monitored

Key questions

Why get involved in research?

Who can participate in research?

Where does research take place?

Will I get better care in a clinical trial?

Is research safe?

How long do studies last?

Can I still have other treatments?

Is it free to join a research study?

Will I be paid?

Can I be involved in more than one research study?

Who works on clinical trials?  

 

Teletrials for cancer

In Australia, some people are now taking part in teletrials.

A teletrial is where hospitals – regional, rural or city – share a clinical trial and work together to deliver it to their patients all at the same time. This means, for example, you may be on the same trial at your local hospital at the same time as someone 200km away at their local hospital.

The entire medical team involved in the one trial use digital communication, such as video conferencing or telehealth, to closely communicate with each other as one big team.

Teletrials were developed to make joining a clinical trial easier for people in rural and remote locations, but they can make it more convenient for anyone to take part.

You can talk to your cancer specialist about whether there is a teletrial you could join. If you are already involved in a clinical trial, you could ask if parts of it can be delivered by telehealth.

Learn more about teletrials

The clinical trials process

Cancer clinical trials are research studies that use volunteers to test new ways (interventions) to diagnose, treat and manage cancer.

If a trial proves that a test, treatment or other intervention is better than existing options, it may become the new standard of care for patients in the future.

A medicine or another intervention can be developed in a laboratory and tested on animals, but it is only once it has been tested on the human body that we can know it works in people.

It also has to be tested on enough people to show that any benefit is not just a random effect for a single person. 

Types of trials

“When I was diagnosed with cancer, a friend told me about the study. Getting involved was simple. Participating in cancer research is about giving to other people, and I think that’s a very valuable thing.” Phillipa

Phases of a clinical trial

Researchers spend many years developing new treatments or medicines in the laboratory before involving people.

They then plan the clinical trial to progress in a series of steps called phases. Every phase considers whether the risks outweigh the benefits.

Information gathered in each phase determines whether the study can move on to the next phase, and whether the drug or treatment is approved for use. There can be up to four phases, but not all clinical trials go through every phase. 

Phases of clinical trials

Randomised controlled trials

It is important for researchers to know that the results of a study are accurate and not caused by chance. This means they must follow strict guidelines.

Researchers also need to make sure their own – or the participants’ – ideas or beliefs about the research don’t unfairly influence the results. There are various ways to make sure clinical trials are fair and reliable.

Many clinical trials are randomised controlled trials (RCTs). A randomised controlled trial helps prevent bias, so it is the best way to test if a new treatment works.

Bias occurs when the results of a trial are affected by human choice, expectations or other factors not related to the treatment being tested.

What is a randomised controlled trial?

Standard treatment and placebos

Blinded studies

Crossover studies

Non-randomised trials

In a single arm trial, everyone receives the same experimental treatment. This method may be used for phase 1 and phase 2 trials, or where the cancer being treated is rare and it is hard to conduct a randomised trial.

Registry trials

For most treatment trials, you will have the treatment as part of the trial. Another way researchers can compare how well different treatments work is through registry trials.

A registry trial collects information from people with a particular type of cancer who are having routine treatment.

It can’t be used for testing new treatments, but it can answer a range of questions about existing treatments. Your cancer treatment team may talk to you about joining a registry trial.

If you choose to join the registry, you agree to share your health information, such as your medical history, the treatments you are having and the results of tests.

This information will then be compared with information from many other patients to work out which treatment approaches are the most effective.

Registry trials are a cost-effective way to run a clinical trial and they allow many more people to participate in cancer research.

Other types of clinical research

Clinical trials are not the only type of clinical research studies. You may also be invited to get involved in behavioural research or translational research.

Behavioural research

Psychosocial research

Translational research

 

Understanding Clinical Trials and Research

Download our Understanding Clinical Trials and Research booklet to learn more

Download now  Order for free

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