Although informed consent is critical for all research, there is increased ethical responsibility as individuals with intellectual or developmental disabilities (IDD) become the focus of more clinical trials. This study examined decisional capacity for informed consent to clinical trials in individuals with fragile X syndrome (FXS). Participants were 152 adolescents and adults (80 males, 72 females) with FXS who completed a measure of decisional capacity and a comprehensive battery of neurocognitive and psychiatric measures. Females outperformed males on all aspects of decisional capacity. The ability to understand aspects of the clinical trial had the strongest association with the ability to appreciate and reason about the decision. Scaffolding improved understanding, suggesting researchers can take steps to improve decisional capacity and the informed consent process.
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We are grateful to all of the individuals with FXS and their caregivers who participated in this study.
This study was funded by a grant from the Eunice Kennedy Shriver National Institute for Child Health and Human Development (R01HD071987-01A1). The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the National Institutes of Health.
Conflict of interest
None of the authors have any conflict of interests to declare.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent and/or assent were obtained from all individual participants included in the study.
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Wheeler, A.C., Wylie, A., Raspa, M. et al. Decisional Capacity for Informed Consent in Males and Females with Fragile X Syndrome. J Autism Dev Disord 50, 1725–1747 (2020). https://doi.org/10.1007/s10803-019-03930-4
- Fragile X syndrome
- Decisional capacity
- Informed consent
- Clinical trials