The ethical relevance of two types of adverse health effects on research bystanders as applied to HIV, mosquito bednet and organ transplant trials.

Using cases from this symposium, I illustrate a distinction between clinical trials that harm research non-participants' health and clinical trials that reduce a distinct health benefit to research non-participants. This distinction is ethically relevant for the design and justification of clinical trials. The relative stringency of the ethical duty to avoid harm makes it more important, all other things being equal, to avoid harms rather than avoid reduction of benefits. This is especially ethically important as it is often difficult to identify research non-participants who will suffer health harms due to research, let alone obtain their informed consent. In these difficult cases, all other things being equal, we have ethical reason to prefer clinical trials that only reduce non-participants' health benefits to those that only involve harms to non-participants' health. When such trials are not feasible and we are unable to get consent for the significant harms to research non-participants, these (and other) countervailing considerations must be outweighed by substantial social benefits in order for the trial to be ethically justified. Ethical research design must not just be concerned with the magnitude of adverse health effects on research non-participants but also the types of those effects.