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A recent systematic review found that almost half of participants who take placebos in clinical trials experience drug related adverse events (AEs), with 5% of participants dropping out due to ‘drug related’ intolerance. However the placebo per se cannot be the cause of these adverse events. Instead, there are two overlapping likely explanations:

  1. Misattribution. A patient may have an underlying condition whose natural history produces some event (such as a headache), then the patient misattributes the event to the placebo.
  2. Nocebo effects. Having been warned about side effects in the patient information sheets, the patient may expect an adverse event. This negative expectation could then produce the event.

Nocebo effects may be caused—at least partly—by sharing information about AEs in the wrong way. This causes a tension between the ethical requirements of autonomy and non-maleficence. On the one hand, autonomy demands that patients be fully informed about treatment (adverse events). On the other hand, non-maleficence demands that patients be informed about AE’s in the right way. Ethical discussions of informed consent have focused almost exclusively on autonomy and may therefore been violating the requirement to do no harm. I will discuss ways in which autonomy and non-maleficence can be balanced in future clinical trials and ethical debates.

Forthcoming events

Ethox/WEH Seminar - Regulation of AI in healthcare: what should we expect?

Wednesday, 28 August 2019, 11am to 12.30pm @ Seminar room 0, BDI, Old Road Campus, OX3 7LF

Ethox/WEH Seminar - Genomic secondary findings in inherited heart conditions: a recall by genotype study

Wednesday, 04 September 2019, 11am to 12.30pm @ Seminar room 0, BDI, Old Road Campus, OX3 7LF

Oxford Open Doors

Saturday, 14 September 2019, 12.30pm to 4pm

The Nuffield Department of Population Health will be open to the public as part of this year's Open Doors event. Find out how medical researchers use big data to answer important questions about human health around the world.

Pharmaceutical policies in the long run: reflections on 60th anniversary of the Hinchliffe Report

Monday, 11 November 2019, 9.30am to 5pm @ Merton College, Merton Street Oxford, OX1 4JD

Designing and Running Streamlined Randomized Trials

Monday, 13 January 2020 to Tuesday, 14 January 2020, 9.30am - 5pm