Bioethics issues in human studies

Informed consent

When data and samples were stripped off the identifiers, samples and data can be kept (Germany).
If not anonymized, the samples have to be obliterated (Germany).
Samples and data will have to be destroyed and deleted in any case (France, Spain, Italy, Netherlands, Poland).
UK: It depends on the reason for withdrawal. If the subject does not want to participate any longer, data and samples may only be used if subject consented to. Withdrawal by the investigator (e.g. because of an adverse event) does not have any implication for the further usage of sample and data. For analysis, data are flagged as withdrawal either by the individual or by the investigator.
After informed consent was initially given, in case of withdrawal, no special requirements exist (Netherlands).
No clear rules exist in Norway.
Individuals can withdraw but samples remain in the study (Norway).
Samples can be kept (Sweden, UK) but no further analysis can be done (Sweden) unless the subject wants the samples to be destroyed (Sweden, UK).

While some scientists think that it might be the best not to offer explicitly the disposal of the samples after withdrawal of consent to the participant,
others advocate the obliteration of samples and data.
The usage of information and samples collected so far in the analysis of the study was preferable for some scientists.
One even thought that the material donated is a gift and can't be recalled.
Withdrawal of samples from the biobank in large studies (with 60,000 people) is not possible; however it is not used in the analysis.
Retrospective revoke of participation should not be possible because of methodological implications for the study. This would also impair the intension of the other participants.
A new consent should be signed that the data and samples can further be used.