Enhancing informed consent for research and treatment.

Increased scrutiny of informed consent calls for further research into decision making by patients who may be at risk for impairments. We review interventions designed to improve patient understanding of informed consent. A number of studies, within as well as outside psychiatry, have evaluated the effectiveness of specific interventions, as well as possible "predictors" of understanding of consent, such as subject characteristics, psychiatric symptoms, and cognitive impairment. Deficits in patients' understanding of informed consent may be partially related to poorly conceived, written, or organized informed consent materials; these deficits may be remediable with educational interventions. We find that effective interventions include corrected feedback, multiple learning trials, and more organized or simplified consent forms. Educational levels of patients generally correlate with levels of understanding. Even among individuals with psychiatric illness or cognitive impairment, deficits in understanding can be remedied with certain educational interventions. A variety of interventions can enhance understanding of informed consent.