Research Impact


Limits to individual choice in health research involving human subjects

Clinical trials

16 December 2014


Patients in clinical trials tend to have a high drop-out rate which can compromise scientific results. Dr Sarah Edwards provided the key ethical framework for limiting individual choice in designing research involving human subjects. Her work was incorporated into national and international guidelines in research ethics.

It was widely assumed that subjects of clinical trials reserve absolute rights to withdraw from a programme of research at any time and without giving a reason; thus the right to withdraw is treated as a simple extension of the right to refuse to participate all together. This practice risks compromising the results of clinical trials.

UCL researcher Dr Sarah Edwards explored the moral justification for limiting individual choice in order to improve methodological efficiency and promote autonomous participation, especially informed withdrawal. Her work included consideration of what consent means in research participation and of the adverse effects of patients having unconditional 'rights' of withdrawal. She used her findings of this work to suggest that participants should, at consent, assume some responsibility for the internal validity of the trial by at least informing the researcher of any reasons for wanting to withdraw.

This argument was made through two strands of research. In the first, Dr Edwards used a philosophical and legal analysis of contractual relationships to develop the idea that research subjects should, at the time of consent, relinquish some of their unconditional rights to withdraw without compromising their ability to make autonomous choices. The second strand focused on cluster trials, which are a form of trial in which intact groups of people, rather than individuals, are allocated to different treatments. Dr Edwards conducted the first philosophical analysis of fair withdrawal from cluster trials following random allocation, showing that these trials can exacerbate pre-existing inequalities, and the concern with statistical efficiency when selecting clusters should be balanced against the strength and social cohesion of existing communities.

This work has implications for those running clinical trials and those who, eventually, benefit from the medical treatments emerging from these trials. Dr Edwards's research has also benefited individuals participating in controlled trials (almost 638,000 in the UK during 2012) by promoting autonomous participation, especially informed withdrawal, throughout trials, and by protecting the rights and interests of individuals in defined communities recruited for cluster trials. In so doing,  her research has helped to address the problem of 'missing data' from trial drop-outs.

In 2008 the Canadian National Institute for Health funded a project, to develop internationally recognised guidelines on cluster trials, based on Dr Edwards's research. As a member of its working group, she helped draft the Ottawa Statement on the ethical conduct of cluster trials, and focused particularly on Recommendation 14 which obliges researchers and ethics committees to consider the need for added protection and appropriate consent procedures for vulnerable participants. The Statement underpinned the first recommendations of the Food and Drug Administration (FDA) in the United States, guiding all FDA funded cluster trials in the country from 2013. This work was also used in the World Health Organization guidelines on patient safety in research in 2013.

Dr Edwards's research now provides the basis for professional training and has thus improved the development and implementation of clinical trials in the UK. The Health Research Authority, previously the National Research Ethics Service (NRES), oversees the operation of 69 NHS research ethics committees whose approval is legally required for clinical research projects in the UK, and Dr Edwards provides research-based training to members of these NHS and Social Care committees. In 2011, her arguments were included in the NRES policy on participant information, with over 10,800 research projects approved under this framework in 2011-2013. The Association of Research Ethics Committees (AREC), an independent umbrella group for research ethics committees with over 2,500 members, also invited Dr Edwards to provide a guide on cluster trials which is now used for AREC training. She has also trained nearly 500 researchers on research ethics and governance through UCL Partners.

Funders included the UK NIHR UCLH/UCL Biomedical Research Centre.