The experiences of bereaved family caregivers in end-of-life wish fulfilment interventions: a qualitative evidence synthesis using realist principles

Intensive care unit (ICU) family caregivers face substantial psychological burdens. End-of-life wish fulfilment interventions such as the 3 Wishes Project offer a low-cost, humanising approach, yet the mechanisms through which they shape bereaved families’ experiences remain poorly understood. This qualitative evidence synthesis, informed by realist principles, aimed to identify context-dependent generative mechanisms underlying family caregivers’ experiences of end-of-life wish-fulfilment interventions. Following ENTREQ and RAMESES publication standards, we conducted a qualitative evidence synthesis informed by realist principles. We systematically searched PubMed, Web of Science, Embase, and PsycINFO (inception to April 2026) and included eight qualitative or mixed-methods studies reporting bereaved family caregivers’ experiences of the 3 Wishes Project. From these studies, we extracted 45 unique family caregiver quotations (52 quote entries after accounting for six quotations supporting multiple mechanisms). Thematic synthesis was used to generate descriptive and analytical themes, which were subsequently organised into Context-Mechanism-Outcome (CMO) configurations. We used the CASP checklist to assess methodological quality and the GRADE-CERQual tool to evaluate confidence in the review findings. Based on the evidence, six intervention-oriented CMO configurations were identified: narrative re-personalization, role liberation and relationship reshaping, emotional release and continuing bonds, partnership and institutionalized compassion, spiritual substitution and meaning-making, and co-creation and restoration of agency. All six configurations were rated as moderate confidence. The evidence base was limited to a single intervention programme (the 3 Wishes Project) and relied entirely on retrospective, post-bereavement interviews. In the ICU setting, end-of-life wish fulfilment interventions appear to support patient dignity and restore caregiver agency through six interrelated psychosocial processes. However, the evidence is confined to one programme and consists entirely of retrospective designs; future independent real-time evaluations are needed to validate these provisional, context-dependent mechanisms.