Recall of informed consent information by healthy volunteers in clinical trials

QJM. 2008 Aug;101(8):625-9. doi: 10.1093/qjmed/hcn067. Epub 2008 May 16.


Background: Information sheets for clinical research are becoming increasingly complex but the extent to which they are understood is uncertain.

Aims: To assess, as our primary outcome, recall by healthy volunteers of key facts in a patient information sheet in a phase 3 clinical trial. As secondary outcomes, we examined whether there was a difference between medical student and non-medically trained volunteers.

Design: Questionnaire to determine recall by healthy volunteers of informed consent information.

Methods: Eighty-two healthy volunteers participating in a capsule endoscopy study were given a 13 page written information sheet and allowed to asked questions. After indicating they were ready to give consent they were asked to complete a 6-item questionnaire covering the identity and adverse effects of trial treatments and of the procedure, the duration of the trial and value of the inconvenience allowance.

Results: All 82 healthy volunteers were questioned. Of the volunteers, 74 (90%) had university level education and 49 (60%) were clinical medical students. However, only 10 subjects (12%) could name the three trial drugs. The maximum number of risks remembered was 6 (n = 2) of 23. Only 14 (17%) could name three or more potential risks of the medication they might be exposed to, whilst 17 (20%) could identify none. Most subjects (77/82, 90%) identified capsule endoscopy as the trial procedure and impaction/obstruction as its main risk (52/82, 64%). All but one subject (98.8%) could recall the exact value of the inconvenience payment.

Conclusion: A comprehensive information sheet resulted in limited recall of trial risks. Shorter information sheets with a test and feedback session should be trialled so that informed consent becomes valid informed consent.

Publication types

  • Clinical Trial, Phase III
  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Adult
  • Biomedical Research / methods*
  • Clinical Trials as Topic
  • Female
  • Humans
  • Informed Consent / ethics*
  • Male
  • Mental Competency / standards*
  • Mental Recall / physiology*
  • Middle Aged
  • Patient Participation
  • Students, Medical
  • Surveys and Questionnaires