When Mary Elizabeth Williams was diagnosed with stage 4 melanoma, her prognosis was grim. But she came across a clinical trial for immunotherapy—which uses the body's natural defenses to fight cancer—and was declared cancer-free just three months later. Some may be reluctant to take part in a clinical trial due to some well-known myths. Here, she sets the record straight:

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Myth: “If I get into a clinical trial, I’ll be stuck in a placebo group and won’t be treated.”

Fact: "Only a small number of trials employ placebos as a means of measuring a treatment’s effectiveness," says Williams. "They are much less common in studies like mine, involving people with serious health conditions such as cancer. In my trial, every patient received the same medication. And when control groups are part of a study, patients in those groups typically still receive treatment (which may be the usual standard of care) throughout the trial."

Myth: “Clinical trials are a last ditch.”

Fact: "While many trials are open only to patients who are late-stage, or for whom other forms of treatment have been unsuccessful, others are available to patients of varying condition," Williams explains. "Increasingly, doctors are learning to work with patients to tailor a treatment plan that is best for the individual—including exploring trials."

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Myth: “I’ll be locked in even if it doesn’t work or I don’t like the trial.”

Fact: "Both the doctor and the patient can reassess throughout, according to how the patient is feeling and her ability to withstand treatment," says Williams. "It’s just an option—it’s not jail."

Myth: “Forget it; there’s nothing going on in research in my small town.”

Fact: "Concerned that trials are available only to people close to big-name hospitals? Research craves variety, and trials are often conducted in cooperation with several facilities at a time," says Williams. "Mine ultimately involved more than 100 facilities around the world. You can search for recruiting studies based on your condition and location at clinicaltrials.gov."