Ethics of Placebo Use in Palliative Care Research
DOI:
https://doi.org/10.5281/zenodo.22686274Keywords:
placebo, palliative care, research ethics, informed consent, clinical trial designAbstract
Placebo-controlled trials in palliative care raise ethical questions that do not reduce to the general placebo debate, because the population under study is often close to death, symptomatic, and under time pressure that standard risk-benefit frameworks do not fully anticipate. This review examines the methodological case for placebo controls in symptom research, the population-specific objections raised by patient vulnerability and compressed prognosis, and empirical evidence on how dying patients and their families actually experience being asked to enroll in such trials. It also considers the distinct evidentiary role of placebo and nocebo effects in symptom outcomes, including emerging evidence of inequitable nocebo harm linked to inconsistent disclosure practice.
We then survey the field's principal risk-minimization strategies: add-on designs against a background of standard care, time-limited exposure with pre-specified escape criteria, enriched-enrollment approaches, and staged informed-consent procedures. We conclude that these procedural safeguards represent a reasonable working compromise rather than a resolution of the underlying ethical disagreement, and that continued attention to patients' and families' lived experience of these trials should guide future refinement more than further abstract argument.
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