Engelaar, MerelBos, Nannevan Schelven, FemkeLorenzo i Sunyer, NoraCouespel, NorbertApolone, GiovanniBrunelli, CinziaCaraceni, AugustoFerrer Forés, Maria MontserratGroenvold, MogensKaasa, SteinCiliberto, GennaroLombardo, ClaudioPietrobon, RicardoPravettoni, GabriellaSirven, AudeVachon, HugoGilbert, AlexandraRademakers, Jany2025-07-162025-07-162024Engelaar M, Bos N, van Schelven F, Lorenzo I Sunyer N, Couespel N, Apolone G, et al. Collaborating with cancer patients and informal caregivers in a European study on quality of life: protocol to embed patient and public involvement within the EUonQoL project. Res Involv Engagem. 2024 Jun 11;10(1):59. DOI: 10.1186/s40900-024-00597-92056-7529http://hdl.handle.net/10230/70927Background: Patient and public involvement (PPI) has become an essential part of health research. There is a need for genuine involvement in order to ensure that research is relevant to patients. This can then improve the quality, relevance, and impact of health research, while at the same time reducing wasted research and in doing so bringing science and society closer together. Despite the increasing attention for this involvement, it is not yet common practice to report on proposed activities. An article reporting planned PPI could provide guidance and inspiration for the wider academic community in future activities. Therefore, this current article aims to describe the way in which PPI principles are incorporated in the research project called "Quality of Life in Oncology: measuring what matters for cancer patients and survivors in Europe (EUonQoL)." This project aims to develop a new set of questionnaires to enable cancer patients to assess their quality of life, entitled the EUonQoL-Kit. Methods: The first step is to recruit cancer patients and their informal caregivers as co-researchers in order to train them to collaborate with the researchers. Based on their skills and preferences, they are then assigned to several of the project's work packages. Their individual roles, tasks, and responsibilities regarding the work packages, to which they have been assigned, are evaluated and adapted when necessary. The impact of their involvement is evaluated by both the researchers and co-researchers. Discussion: PPI is a complex and dynamic process. As such, the overall structure of the research may be defined while at the same time leaving room for certain aspects to be filled in later. Our research is, we believe, relevant as co-researcher involvement in such a large European project as EUonQoL is a new development.application/pdfeng© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1186/s40900-024-00597-9Co-researchersOncologyPatient and public involvementPatient engagementPatient participationinfo:eu-repo/semantics/openAccess