The SISAQOL-IMI glossary: harmonising terminology for patient-reported outcomes in cancer clinical trials

Background This study presents the development of a glossary designed to harmonize terminology, foster consensus and support the successful implementation of the Setting International Standards in Analysing Patient-Reported Outcomes and Quality of Life Endpoints in Cancer Clinical Trials-Innovative Medicines Initiative (SISAQOL-IMI) guidelines. Methodology SISAQOL-IMI consortium representatives from 41 international organisations were invited to participate in the development of the glossary. From 2021 to 2024, the glossary was developed through iterative processes, guided by consortium members input and formally updated twice yearly. A template with categories for term, acronym, topic, scientific definition, plain language definition, examples and references/sources was applied and were accessible for input throughout the process. As project documents such as draft guideline recommendations were updated, new terms for the glossary were identified. Definition of terms were primarily sought from a predefined hierarchical list of references and acknowledged resources, such as existing glossaries, prior to seeking other references. Patient representatives and patient advocates from The Workgroup of European Cancer Patient Advocacy Networks contributed to plain language definitions. Results The glossary development resulted in 227 terms with scientific and plain language definitions, which are integrated into the online SISAQOL-IMI guidelines. During the initial development phase, of 205 terms, the project’s work package teams agreed on 166 (81%) and had diverging views on 39 (19%). Discussions were organized to reconcile disagreements. The glossary proved essential in 1) helping patient representatives better understand and engage in the consensus process, 2) aligning terminology during the pre-testing of preliminary recommendations, and 3) clarifying terms during the final language harmonisation of the recommendations. Conclusions The glossary was pivotal in ensuring a common understanding of terminology throughout the SISAQOL-IMI project. It serves as a critical resource for enhancing clarity and successful implementation of the SISAQOL-IMI recommendations, ultimately advancing the role of patient-reported outcomes in improving the quality of cancer clinical trials.