Decisional Capacity of Women With Fragile X Surpasses That of Men, Study Says

Women with fragile X syndrome surpass men in their decisional capacity for informed consent about participation in clinical trials, a study says.

The findings of the study, “Decisional Capacity for Informed Consent in Males and Females with Fragile X Syndrome,” were published in the Journal of Autism and Developmental Disorders.

Individuals should be capable of providing informed consent to enroll in clinical studies. However, in trials that involve participants with intellectual or developmental disabilities, there is not enough guidance on how to appropriately assess understanding and capacity to consent.

Obtaining informed consent from a patient with intellectual or developmental disabilities may require researchers and physicians to facilitate information access and comprehension (for example, using simple language to explain what is required, reading information aloud, or summarizing it). For this reason, in many cases it is still the caregiver or guardian, rather than the patient participating in the study, who gives consent.

“But with appropriate supports, those with [intellectual or developmental disabilities] may be able to make decisions about participation in research studies, and researchers have a moral and ethical obligation to maximize their participation in the process,” researchers argued.

In this study, scientists at RTI International (formerly the Research Triangle Institute), a nonprofit organization in North Carolina, and collaborators set out to investigate the factors that might affect the decisional capacity for informed consent of both men and women with fragile X regarding their participation in clinical trials.

The study enrolled 152 adolescents and adults with a confirmed diagnosis of fragile X — 80 males and 72 females, mean age 20.45 years. Study participants were recruited by several means, including family outreach, online postings with national advocacy groups, and direct enrollment at the National Fragile X Foundation family conference.

All patients completed neurocognitive and psychiatric tests to assess their decisional capacity, cognitive, executive, learning and memory capabilities. All study participants also underwent a thorough autism clinical evaluation. Data on social behavior, anxiety, and adaptive behavior were obtained through caregivers’ reports.

Results showed that females’ performance surpassed that of males in all categories of decisional capacity. However, the domains in which females had their best and worst performances (understanding and appreciation/reasoning) were the same in males.

“Almost all females and about half of males received full credit on understanding items related to technical details of clinical trials, such as the duration of the study (82% females; 49% males), procedural elements (88% females; 55% males), benefits (86% females; 51% males), risks (86% females; 58% males), and ability to withdraw (81% females; 51% males),” researchers said.

However, more abstract concepts were more difficult to understand, including “the purpose of the trial being for research rather than clinical care (36% females; 3% males), placebo (53% females; 6% males), and societal benefit (49% females; 5% males),” they said.

Further correlation analysis showed that in general, the ability to understand details of clinical trials was strongly linked to the ability of appreciating and reasoning about the decision. Researchers found that “scaffolding” — repeating information or using visual cues — improved patients’ ability to understand information.

“Researchers working with individuals with [fragile X] and other [intellectual or developmental disabilities] should consider a multi-method approach to providing information about what will be expected of the individual during the trial — this should include written as well as oral information and use of visual cues whenever possible,” researchers said.

“Future studies should be focused on promoting better understanding and increased decisional capacity for individuals with [fragile X] and other [intellectual or developmental disabilities], with the ultimate goals of improving integrated research practices and enabling those with [intellectual or developmental disabilities] to be more informed about their health care decisions,” they concluded.