Individuals without capacity excluded from potentially beneficial trials

Sep 11 2012

By Sarah Guy, medwireNews Reporter

Individuals who lack the capacity to consent to taking part in clinical trials could be missing out on the opportunity to receive potentially beneficial interventions, shows UK research.

Analysis of the recruitment process for the FEVER study, an influenza vaccine-based randomized control trial of elderly care home residents in the UK showed significant bias since the setting for recruitment is associated with the prevalence of dementia, say the researchers.

Furthermore, "the main and avoidable barrier" to individuals without capacity being included in the trial was the inability to identify a relative able to give assent, or unwillingness of staff at the care home to assent on behalf of the person, reports the team.

"People with cognitive impairment are already disadvantaged enough without being also excluded from research and also the benefits of research on their conditions," say Alastair Macdonald (Kings College London, UK) and colleagues in the Journal of Medical Ethics.

Of 968 individuals aged 60 years or above who were assessed for capacity to take part in FEVER, 602 (62.2%) lacked capacity. These patients were more likely than consenting individuals to be older (mean 83.6 vs 90.8 years), female (66.2 vs 50.2%), and live in an Elderly Mentally Infirm residence usually occupied by those with dementia and behavior problems (83.1 vs 54.3%).

These data indicate "disproportionate" exclusion of such individuals, say Macdonald and team, which is important "since... the response of people with dementia to vaccination may be different."

Among patients without capacity who were not excluded from the study for other reasons (n=557), 26% were considered by the research nurses to be likely to physically resist the procedures involved in FEVER, while the majority, 55%, were not included because neither a relative could not be found to act as a proxy, nor was a staff member happy to give assent. A small group of 40 (13%) were entered into the study via care home staff assent.

"This may have reflected a careful decision about the residents' likely wishes if they had had capacity, but could equally have been because of reluctance to take responsibility for any adverse consequences," remark the authors.

The team suggests that expanding the roles of the UK Mental Capacity Act advocates to include assenting to trials participation, or giving the responsibility to a scientific panel associated with the particular study and independent of funders, could be possible solutions.

Licensed from medwireNews with permission from Springer Healthcare Ltd. ©Springer Healthcare Ltd. All rights reserved. Neither of these parties endorse or recommend any commercial products, services, or equipment.