Hearing the voices of children: self-reported information on children's experiences during research procedures

__Introduction:__ In paediatric research, there is a tension between what you can ask from a child and what is needed for the development of evidence-based treatments. To find an optimal balance in conducting clinical research and protecting the child, it is necessary to have empirical data on children's experiences. Until now, there are scarce empirical data on the experiences from the perspective of the child. In this manuscript, we describe the protocol of a twophase study measuring children's self-reported experiences during research procedures. __Methods and analysis:__ In the first phase of our study, we aim to interview approximately 40 children (6-18 years) about their self-reported experiences during research procedures. In the second phase, we will develop a questionnaire to measure children's experiences during research procedures in a quantitative way. We will use the interview outcomes for the development of this questionnaire. Next, we will measure the experiences of children during seven research procedures with this questionnaire. A one-month followup is conducted to investigate the emotional impact of the research procedures on the children. Children will be recruited from different research studies in three academic children's hospitals in the Netherlands. __Ethics and dissemination:__ The ethics committee of the VU University medical center evaluated both studies and indicated that there was no risk/discomfort associated, stating that both phases are exempt from getting