Every study in the HNRU is unique, and there is no generic answer to this question. Some studies may be a questionnaire or others may be more invasive. Part of the study consent process will be to fully explain any and all potential risks to you. These risks could include something physical like the brief pain of a needle for a blood draw, or potential for bruising afterward. It is important that you understand the risks of the study you are interested in and ask lots of questions to your study team. All of our study protocols have been reviewed by the University of Guelph's Research Ethics Boards and all risks have been considered and minimized to the best of our ability.