Objective: Informed consent is ethically and legally required for all biomedical and health research involving human participants. This study analyses the realization of informed consent in health research from the point of view of healthy, voluntary adult participants. Empirical studies from this point of view are still rare.
Design: A population-based questionnaire survey.
Participants: The study population consisted of 1410 men and women aged 57-78 years who are participants in a randomized controlled intervention trial on the effects of physical exercise and diet at Kuopio Research Institute of Exercise Medicine (eastern Finland).
Methods: The data were collected in 2005-2007 using a questionnaire. The questionnaire was given to all able and willing participants (n = 1324) who were still involved in the exercise and diet study at the 3-month intervention visit. The response rate was 91%.
Results: The defined key elements of informed consent were information, understanding, competence, voluntariness and decision-making. A majority of the participants estimated that these key elements were successfully realized in the exercise and diet intervention study.
Conclusions: Despite the general satisfaction with the informed consent process in the exercise and diet intervention study, a minority of the participants were dissatisfied with the information they had received or did not understand this information completely. These findings highlight the essential question: Did all of the participants truly give their genuine informed consent? This carefully executed study reveals objectively the difficulties in distribution of information to healthy adult volunteers.