Decision aids in clinical trials can enhance informed consent

Tools help match decisions to subjects' values

As research participants confront ever more-complicated clinical trials, they also encounter longer, more complex consent forms. Concerns that informed consent isn't necessarily enhanced by these documents has led researchers to seek more useful ways of educating subjects about the study they're considering.

One alternative, the decision aid (DA), uses graphic representations and worksheets to explain a study in a user-friendly way, and to help guide a potential subject to an informed decision about whether to participate.

In recent years, studies have revealed a tension between disclosing all necessary information to study participants and making that information understandable, says Jamie Brehaut, PhD, a scientist in clinical epidemiology at the Ottawa Health Research Institute in Canada, and associate director of the Ottawa Patient Decision Support Laboratory.

"Anybody who's on an IRB will likely have experienced the feeling that the consent materials these days are getting more complicated," Brehaut says. "They're getting longer and more detailed. Along with that though is the realization now that sometimes people who are participating in trials don't understand even some of the basic tenets of what they're participating in."

While there have been initiatives to improve the readability of consent documents and to make their formats more user-friendly, Brehaut says it's time to move beyond those efforts at creating what he calls "barely informed consent."

"We need to think about good decision making," he says. "That's what I think the goal should be when we're talking about helping a person decide whether to participate in a clinical trial."

Proponents of decision aids say they do a better job of outlining not just the particulars of a study, but what values are important to an individual participant weighing whether to sign up. They also describe other options, such as the standard care or no treatment at all, that participants could choose instead.

"Clinical trial consent forms traditionally present comprehensive information only about the clinical trial in consideration," says Ilona Juraskova, PhD, a senior post-doctoral researcher in the Medical Psychology Research Unit at the University of Sydney in Australia.

"In contrast, the DAs present all options available for the patient/consumer, including the status quo, and make the reasons for and against trial participation explicit. Furthermore, risk information is presented in numerical, graphical, and visual formats, which have been proven to be the most easily understood and integrated into decision making."

She says decision aids could be particularly useful in more complicated studies.

"The more complex the decision, the more useful a DA will be," she says. "For complex trials with many treatment arms, or where there are large potential costs of participation, DAs may be particularly helpful."

'Preference-sensitive decisions'

Decision aids have been used for years to help patients decide on a course of treatment in situations with several possible options, depending on the preferences of the patient.

"It's for those what we call preference-sensitive decisions that patient treatment decision aids were developed," Brehaut says. "What they do is they improve decision making under situations when there's no obviously correct answer."

Brehaut says that there are three key points to a good medical decision that can be addressed by decision aids:

  • an understanding of the key aspects of the decision;
  • an accurate idea of what the probabilities of the different outcomes are;
  • finding a match between the choice being made and the kind of outcome the patient thinks is most important.

"(The aid) can have exercises to make explicit to people the outcomes that they're interested in, as individuals" Brehaut says. "Which outcomes do you particularly value?"

The tools themselves can be paper-based, often in a workbook format, or on-line exercises. They're usually not a shorter, simpler version of an informed consent document—in fact, Brehaut says, it's intended that the patient will spend some time with a decision aid.

"It's not going to result in a lot of time savings in terms of arriving at the decision," he says. "What it does do is it helps people make better use of their time. So rather than working through a complex (informed consent) document that doesn't provide you any help to work through it, the decision aid has the potential to allow people to make good use of their time."

While research has shown that patients using decision aids have increased knowledge about and satisfaction with their medical decisions, Brehaut says there has been relatively little research done on the possible benefits of using DAs to help people decide whether to enroll in a clinical trial.

To get at that question, Juraskova and her team, which includes professors Phyllis Butow and John F. Forbes, have developed a decision aid for use in the International Breast Cancer Intervention Study II (IBIS-II), a multicenter, randomized clinical trial being conducted in the United Kingdom, Australia, and New Zealand. The trial is investigating the use of anastrozole by postmenopausal women at increased risk of breast cancer.

Juraskova's team created decision aids to help women decide whether to sign up for IBIS-II.

The aids included explanations of all the possible options available to women in the trial, including the standard care and the study drug. It also explained the concepts and terms involved in clinical trials and provided worksheets to help women work through their own preferences.

Graphic representations help take abstract ideas like risk and put them into a context for potential subjects. A page might show a field of dots, with the percentage of people who might experience certain side effects shaded in. "Balance scales" help rate perception of risks and benefits to "weigh" a decision. The aids include examples of worksheets filled out by hypothetical subjects, one showing a subject leaning toward participation, one leaning against enrolling.

In designing the DA booklets, Juraskova's team reviewed findings from studies in which cancer patients described questions they would ask about clinical trial participation and how they would like to see information presented.

Juraskova's team tested the decision aids among women who had already participated in an earlier version of IBIS, to judge their use in addition to a standard informed consent document.

A substantial majority (87%) found the DA helpful in understanding the informed consent document and 90% preferred receiving both documents to the informed consent document alone.

Respondents said that not only was the decision aid easier to understand, but that it would make a good reference once a person had enrolled in the trial, Juraskova says.

International standards

Brehaut predicts that similar studies will explore the usefulness of decision aids in clinical trial decision making, as part of the larger effort to improve informed consent in research.

"I think there is an understanding out there that informed consent process needs to be improved and the decision aid approach seems to be potentially a fruitful way to look at it," he says.

An IRB confronted with a decision aid in a clinical trial should check to be sure that it has been created according to criteria set by the International Patient Decision Aids Standards Collaboration (

"This represents an international consensus on best practice," Juraskova says.

Brehaut says the effectiveness of a decision aid should be measured by indications of good decision making, not just whether the document is readable, or whether subjects can recite facts about the trial.

"Does the decision aid have a specific exercise for determining what outcomes a patient particularly values?" he asks. "Which are the outcomes they particularly want to avoid, which are the ones that they are particularly interested in?

"If you're testing if a decision aid works or not, there should be some sort of measure for understanding whether the decision aid process increases the match between the outcomes that they value and the thing they ultimately choose."

Juraskova notes that proposed studies using decision aids also should outline realistic ways of implementing them. DAs do involve a time commitment, especially more complex ones, which are accompanied by a video or are computer-based.

She says that costs of creating a decision aid may be prohibitive in smaller trials, but her group hopes to create a template based on their work with IBIS-II that might help make the development of other DAs easier and less expensive.