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Pros and Cons of Participating in a Clinical Trial

Science needs more older adults. But what are the risks and benefits of volunteering?

spinner image A man sitting on a bed in a doctor's office talking to a female doctor about participating in a clinical trial
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With several coronavirus vaccine candidates advancing to the third and final phase of clinical trials, researchers are ramping up their efforts to ensure that older adults are well represented among the tens of thousands of volunteers rolling up their sleeves to test the various vaccines. But boosting participation among the aging population may prove challenging for these studies.

Enrollment of older adults in clinical trials, across the board, has historically lagged behind what experts deem ideal. And despite recent efforts to improve representation, it's “still an ongoing problem,” says Lindsay Clarke, vice president of health education and advocacy at the nonprofit Alliance for Aging Research — especially considering older adults take more prescription medications than younger ones and are more likely to have a disease or ailment that could benefit from breakthrough therapies.

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Sometimes it's personal barriers that prevent older adults from participating — a disability or lack of transportation may make it difficult for an individual to get to and from the trial site. Other times, the study design itself blocks older adults due to restrictions on age, underlying conditions or the use of certain medications. Either way, inadequate representation in medical research can have serious implications.

"When we don't have the clinical trial data or are not involving the relevant populations, then clinicians end up having to guess about what the right dose is for their patient, what the potential side effects might be, what the potential interactions with other drugs that they might be taking can be,” Clarke says.

Though older adults clearly are needed in clinical trials, it's also important that individuals understand the risks and benefits of participating. If you are thinking about signing up for a clinical trial, here are a few pros and cons to consider.

Pro: You could be among the first to receive a new drug or therapy

For many conditions — whether it's COVID-19 or Alzheimer's disease — researchers are still searching for therapies that can help prevent an illness or lessen its severity. And clinical trial participants “can have access to really exciting new science that others aren't getting access to yet,” Clarke says.

Your participating in a trial also allows researchers to study how these cutting-edge drugs, devices or procedures will work across different ages, races and backgrounds.

"If a drug has only been tested in younger people, then how do you know it's also going to be good [in someone who is older?],” says Raymond Yung, M.D., a professor of geriatric medicine at the University of Michigan and associate director of research at the Department of Veterans Affairs’ Ann Arbor Geriatric Research Education and Clinical Center.

Take vaccines, for example: Eric Topol, M.D., a clinical trial expert and founder of the Scripps Research Translational Institute, says “there's a very marked difference in immune system response as we age.” This is why testing vaccines in older adults is key to understanding how effective the medicine will be once it is made widely available to the public.

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Con: The treatment may not work, or you could get a placebo

On the flip side, just because you enroll in a clinical trial doesn't mean you are guaranteed to receive the treatment that's being tested.

Many clinical trials compare the new treatment or intervention to a placebo. (A placebo is a substance that has no therapeutic effect, such as a sugar pill or saline solution shot.) So when you enroll in a clinical trial, you could be assigned to this comparison group, called the control group, and not receive any treatment at all. Other trials use existing treatments and interventions as the comparison group.

Also, the new treatment or intervention is not guaranteed to work better than a placebo or existing treatment.

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Pro: Your health will be closely monitored throughout the study

Oftentimes patients first learn about a clinical trial through their own health care providers, and once enrolled they find that the trial's medical research team becomes like “an extension of their care team,” says Sumita Khatri, M.D., director of the Cleveland Clinic Asthma Center and a research subject advocate for the Clinical Research Unit at Cleveland Clinic.

With all of the extra monitoring and wellness checks, Clarke says volunteers may end up receiving “more comprehensive care in the trial than they would if they weren't participating.”

It's important to consider the costs of this care. Often, these exams come at no additional charge to clinical trial volunteers. Federal law requires most health insurance plans to cover routine patient care costs such as doctors’ visits in approved clinical trials, according to the National Cancer Institute, which is part of the National Institutes of Health (NIH). The same goes for Medicare. And the study will often cover extra tests or scans needed for research.

However, whether participants are responsible for any out-of-pocket costs or copays is an important question to raise with researchers ahead of enrolling, since this often varies, depending on the participant's insurance and the trial's design.

"It's a long process. It's an involved process,” Khatri says, “But because of the multiple visits, you're monitored way more than you would be as a layperson just, you know, walking around in the world.”

Con: You could experience unpleasant side effects or an adverse reaction

No matter how closely you are monitored, the drug or therapy being tested could cause an unpleasant side effect, ranging from minor (such as a sore arm at the injection site) to more severe, called an adverse reaction. (An example of this: AstraZeneca's phase 3 coronavirus vaccine trial was recently paused to investigate what the pharmaceutical company called “a single event of an unexplained illness,” widely reported to be transverse myelitis, a disorder caused by inflammation in the spinal cord. The trial has since resumed in several countries.)

It's important to note that most serious reactions and complications are typically discovered in the earlier phases of a clinical trial, when the safety of a drug or device is tested in a smaller population, Khatri says.

Also: Researchers are required by the federal government to follow strict protocols designed to protect the health and safety of study participants. This protocol is explained to prospective participants during the informed consent process, where members of the research team discuss the volunteer's role in the trial and any risks associated with participation. The NIH's National Institute on Aging (NIA) has a comprehensive list of questions to ask during this process (or any time when deciding whether to join a clinical trial).

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If you choose to participate, you will be asked to sign an informed consent document. Sometimes researchers will mail this form to potential participants ahead of meeting in person, so the interested volunteer can have time to read and digest the information and discuss the trial with their loved ones, Yung says. However, the NIA makes it clear that the document is not a contract, and even after signing the consent form, participants “can leave the trial at any time and for any reason” without judgment or penalty.

"The fact that it is something new means that there is always risk, and a risk that we may not be able to anticipate,” Yung says. “And so you have to understand what risk level you are willing to take.”

Pro: Your participation could help others

There are benefits beyond the possibility of bettering your own health. Your participating in medical research allows doctors and scientists to learn more about a condition that likely affects a lot of people. And if it's a genetic condition being studied, your participation could affect others close to you.

"It's sort of an altruistic sense of being able to help others not to have to suffer through what [you] are suffering,” says Jay Magaziner, professor of epidemiology and public health at the University of Maryland School of Medicine and director of the Center for Research on Aging.

"I think that part of our responsibility, too, for being part of a thriving society is to think about not just ourselves, but think about what we can do to help others, especially in cases where it doesn't put us at undue risk,” he adds.

Con: Participating in a clinical trial can be inconvenient

Each trial has different requirements when it comes to time. Some studies last days, while others take years. Some require long in-person appointments and tests, while others can be done over the phone in a matter of minutes. So it's important to find out how much time the study will demand and decide whether you have that kind of time to spare.

A trial may also require travel to a medical center or research hospital. If that is the case, ask whether you will be reimbursed for gas and parking. Some clinical trials may even reimburse you for your time and participation, but this varies. (In rare cases, clinical trials may request that volunteers pay for participation. If this come up, there are certain guidelines researchers should follow.)

And if you can't drive yourself to the research site, ask about transportation options. The study coordinators may be able to make arrangements to get you where you need to be.

Some questions to ask before signing up for a clinical trial

  • What is the goal of the study? What are researchers trying to find out?
  • What is required of participants?
  • What treatment is being tested? Will it hurt? And will participants have access to the treatment after the study?
  • What are the chances I will get the treatment? What are the chances I will be a part of the control group?
  • What are the possible risks, side effects and benefits of the study treatment? And how does it compare to what's currently available?
  • How could being in this study affect my daily life?
  • How long will the clinical trial last?
  • Will there be any travel or additional costs while I am in the trial? If so, will they be covered?
  • Where will the study take place? Will I be required to stay in the hospital? Who will be in charge of my care?
  • Will the study help arrange transportation to the research site?
  • When will the results of the study be available? How will I be told about the results?
  • If I do not qualify for this study, where can I find out about other trials?

For a full list of questions interested volunteers might want to ask, visit the National Institutes of Health website.

Source: NIH

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