2010, reported a preference for a broad, 'one off' consent at the time of donation to a biobank over giving specific consent for each new study. a meta-analysis of the qualitative sociological literature on public and patient attitudes to biobanking published 2002-9 reached a similar conclusion: 'few people demanded recurrent, project-specific consent and few wished to place limits on the uses to which their tissue could be put'. however, these studies did not present dynamic consent to their respondents as an alternative to a broad consent. there have been some criticism of dynamic consent by a norwegian team of researchers, who argued that dynamic consent would be an unwanted burden on participants and a waste of time for researchers. 'in a dynamic consent model, participants will be asked for consent continuously, simply because each new project is a new project. thus, they will be asked to re-consent both for trivial and essential reasons, and often the former'. however, this opinion was based on an erroneous understanding of dynamic consent as requiring consent for each new study, rather being able to be tailored to the needs and ethical requirements of a particular study. steinsbekk et al. in their publication criticising dynamic consent also argued that rather than increasing the number of people taking part in research, dynamic consent may have the opposite effect. 'being confronted with the detailed complexity of biomedical research, and being asked again and again for an 'opinion' (a consent), it is likely that at least some people will struggle with feelings of falling short – that their own competence or knowledge do not suffice. this could easily be interpreted as a 'lack of respect' for the passive participant, and result in lower participation as people would rather choose to stay away from such studies than face shortcomings.' researchers raise concerns about the impact of consent withdrawal (more easily facilitated by dynamic consent) on the integrity of their research data sets. there are also questions about the equity impacts of a dynamic consent approach, including fears that the 'digital divide' may impede its utility for some participants. one paper has looked at the potential use of a dynamic consent approach in relation to legacy collections of human tissue and data from australian aboriginal and torres strait islander peoples, noting that access to the internet and suitable technology may be a challenge in remote communities. the increasing need for a consent mechanism that can accommodate family or other group-based decision making instead of or in addition to individual consent presents another avenue for development of dynamic consent. rebuttals there are a number of important limitations to consider when evaluating the results of studies of consent practices. in many cases, while a statistically significant preference for one form of consent over another can be found, this is not necessarily indicative of a clear majority preference. for example, haddow et al., 2011, characterised their reported consent preferences as 'not strong'. another study reported that while 58% of respondents described re-consent as 'a waste of time', 51% also felt that being asked for it was an indication that they were 'respected and involved' participants in research. in the case of prospective public attitude surveys on biobanking, of which there are many in the existing literature, johnsson et al., 2010, found that reported willingness to share data and tissue for research was prone to both overestimating and underestimating recorded participation levels in different cases, leading to questions about the usefulness of this type of research in making predictions of future behaviours. evaluation of dynamic consent researchers have proposed an evaluation and reporting framework for dynamic consent in order to support and structure future assessment of the effects of the approach. australian genomics is evaluating the effects of its 'ctrl' platform compared with standard consent processes. a 10 year evaluation of the concept by mascalzoni et al. found that even though a low change rate was reported in the baseline, participants valued the possibility of changing their informed consent choices.