Patients' attitudes toward informed consent for intravenous contrast media

To assess patient attitudes concerning informed consent and the risks of ionic and nonionic contrast material, 1,197 completed questionnaires were obtained from individuals either awaiting contrast injection or waiting for other services.

Six different questionnaire formats were administered, including two detailing the specific risks of ionic and nonionic contrast, respectively. Different questionnaire formats were used to assess whether the severity or the probability of adverse consequences had more influence on a patient's desire for information. Two questionnaires evaluated the effect of comparing medical risks to equivalent risks from everyday nonmedical activities.

Regardless of questionnaire format and the severity of potential risk, the large majority of individuals want some information before contrast injection, and approximately half view such information as essential. Individuals reacted more to the probability of a potential reaction than its severity, and to items ordered toward the end of a particular questionnaire than at the beginning.