Informed consent for percutaneous lung biopsy: comparison of two consent protocols based on patient recall after the procedure

Abstract

Objective: Informed consent is now required for the majority of radiologic procedures, but few studies have evaluated the efficacy of informed consent protocols. We compared our standard consent protocol of obtaining consent prior to percutaneous lung biopsy with a modified protocol by using patients' recall of procedure risks after the biopsy as an indicator of patients' comprehension.

Subjects and methods: The study sample consisted of 50 patients who underwent percutaneous lung biopsy between December 1992 and June 1994. Twenty-seven patients received our standard informed consent procedure in which four important procedure risks were described briefly using our standard method. Twenty-three patients underwent a consent procedure that had the following modification. After the four procedure risks were described, the patient was tested verbally until all risks could be recited to the physician. This change required 5 additional min at most. In both protocols, efficacy of the procedure was evaluated by testing patient recall 4 hr after consent was obtained. We also assessed any effect that might have been introduced by differences between the groups, age, sex, time between consent and recall, and complications during the procedure.

Results: Patients' recall was significantly better in the modified consent group than in the standard group (p = .005). This result could not be attributed to differences in age, sex, or time between consent and recall. There was a trend for improved recall in patients with complications. This trend did not appear to influence our principal finding.

Conclusion: The standard consent procedure for lung biopsy appears inadequate when patients' recall of procedure risks later is used as a measure of the patients' comprehension. Based on this study, the informed consent process may be improved substantially by teaching patients to recite the procedure risks to the physician as part of the informed consent protocol.