We found broad majority support—ranging from 68% to 83%, depending on the scenario—for a societal policy of family surrogate consent for AD research. A previous survey of adults at increased risk for AD also showed majority support for family consent for the same four SBR scenarios.17
Another previous study of research participants at risk for AD19
found very high willingness to participate in SBR of relatively low risk. A survey in Quebec18
showed similar results but its emphasis on examining a variety of surrogate types (legal guardian, family) makes it difficult to compare with our results.
The responses from the societal and self perspectives are closely related, but they should not be treated as equivalent. Personal willingness to participate is not a proxy for views about the ethical appropriateness of SBR because many people may choose not to participate for a variety of reasons. If the point is to characterize public opinion on the ethical permissibility of SBR, then respondents’ views from a societal perspective should be primary. Of course, it may not be ideal if many more people are willing to allow SBR as a societal practice than those who are willing to participate. However, even for the vaccine study scenario, in which the gap is greatest, the majority (57%) of respondents still desire to participate.
The significant underrepresentation of racial and ethnic minorities in AD research is a perennial concern.20
Recent studies have shown that racial and ethnic minorities, despite the legacy of abuses such as the Tuskegee study, are similar to whites in their attitudes toward and participation in research.25,26
We found that regarding the social policy of family surrogate consent for SBR, the differences among racial and ethnic groups are small and the overall level of support is high. In terms of a desire to participate in SBR, the overall pattern among minority respondents is a somewhat lower willingness to participate. However, responses vary a great deal by scenario. For instance, although black Americans are significantly less likely to volunteer for a drug RCT, they appear more likely than whites to endorse the gene transfer neurosurgical study for AD with family consent (and are no less willing to participate).
Leeway is an important concept because it may signify a subject’s recognition that the future cannot be pinned down in detail and it allows subjects to convey their trust in their surrogates who will have more complete information at the time of actual decision-making. The majority of our respondents would allow some or complete leeway for all the scenarios. However, it should be noted that a significant minority (up to 45% for the gene transfer scenario) would not allow leeway.
Those who are willing to participate in research are highly likely to allow leeway. Relational factors (such as feeling understood by their potential surrogates) clearly play a role as well—and this may have important consequences on how we view current practices. Because there is ample cross-sectional evidence that even impaired dementia patients generally express “reasonable” preferences (i.e., similar to healthy controls) for treatment27
and for research participation,28
if such preferences are predictive of a desire for conferring leeway then the current practice of surrogate consent with subject assent seems well supported. However, only a longitudinal study would provide direct evidence regarding whether a potential subject’s current preference (as reflected in the subject’s assent) is reflective of a longstanding desire for granting leeway.
Even among those who state that they do not desire to participate in SBR, a significant minority (over a quarter) are willing to confer some or complete leeway on their future surrogates. If these subjects are added to those who are willing to participate in the four SBR scenarios, the proportions of potential participants would rise to approximately 80% for the LP study, 88% for the drug RCT, 79% for the vaccine study, and 74% for the gene transfer study. A recent study of elderly subjects from senior centers and primary care clinics regarding an LP SBR scenario found similar results.22
However, this point needs to be balanced by the fact that the surrogates of those who are willing to participate and are willing to grant leeway will have the latitude to override that willingness to participate; leeway does not necessarily imply an increase in enrollment.
This study’s main limitation is that the scientific and policy issues surrounding surrogate consent for research are quite complicated. This brief survey captures only a snapshot impression regarding SBR. It may be that as people learn and reflect more, their attitudes may change. We are therefore currently conducting a series of all-day deliberative democracy sessions with laypersons and caregivers regarding SBR.29
Another limitation of the study is that it focuses on dementia research and may not generalize to other areas of SBR.30,31
An important strength of this study is its large and representative sample with an excellent response rate. The Federal government is revisiting the issue of surrogate consent and recently solicited public input.32
As a nationally representative study on the topic,our study provides new data for an important policy discussion.
The primary ethical goals in overseeing SBR are to minimize the potential harms of SBR (already mandated by the current regulations) and to minimize the potential for enrolling persons whose values may not be compatible with participation in SBR. In this regard, the current evidence, including the results of our study, provides some guidance. First, it appears that even for invasive studies the prior probability of an older American’s willingness to participate in SBR is high. Second, even among those who are not willing to participate, there is a sizable minority who are willing to confer some leeway on their surrogates. More research on attitudes toward leeway may provide further guidance to policy makers and to researchers at the time subjects are approached for research. Third, even when patients suffer from dementia with impaired decisional capacity, they may still retain some ethically relevant abilities. Persons with AD express personal choices regarding research participation that are similar to those expressed by competent adults, suggesting that risk-related preferences are relatively preserved.28
Thus, the practice of requiring the assent of even incapable subjects may provide another level of assurance. Patients with AD may also have relatively preserved abilities to appoint a trusted relative to help make research decisions for them.33
Finally, it is quite likely that persons acting as family surrogates will be protective and provide a gatekeeper function.17
Future research should aim to provide further guidance on how to minimize the enrollment of those whose values are not compatible with SBR.