Background: Research ethics committees are commonly perceived as a ‘barrier’ to research involving seriously ill children. Researchers studying seriously ill children often feel that committees view their applications more harshly compared to applications for research with other populations. Whether or not this is the case in practice is unknown. Aim: The aim of this study was to explore committees’ concerns, expectations and decisions for research applications involving seriously ill children submitted for review in the United Kingdom. Design: Content analysis of committee meeting minutes, decision letters and researcher response letters. Setting/participants: Chief investigators for National Institute of Health Research portfolio studies involving seriously ill children were contacted for permission to review their study documents. Results: Of the 77 applications included in this study, 57 received requests for revisions at first review. Committee expectations and concerns commonly related to participant information sheets, methodology, consent, recruitment or formatting. Changes were made to 53 of these studies, all of which were subsequently approved. Conclusion: Our findings suggest that committees review applications for research involving seriously ill children with the same scrutiny as applications for research with other populations. Yet, the perception that committees act as a barrier to this type of research persists. We suggest that this perception remains due to other factors including, but not limited to, the high levels of formatting or administrative revisions requested by committees or additional study requirements needed for research involving children, such as multiple versions of consent forms or participant information sheets.