Understanding what matters to young people with life-limiting and life-threatening conditions: a qualitative study to inform the development of a young person end-of-life capability measure

End-of-life care encompasses a range of services aimed at delivering holistic interventions. Yet, economic evaluations of such services have tended to be focused on health-related outcomes, which may be too narrow to adequately capture outcomes at the end of life. Capability measures aim to capture wider outcomes focusing on what people can do and be in their lives. Capability measures are not yet available for children and young people at the end of life. This study aimed to identify important capabilities for young people aged 14–25 years across the end-of-life trajectory, to inform attribute development for a capability measure for use in economic evaluation of interventions at the end of life. Twenty-one in-depth interviews were undertaken with young people aged 14–25 years with a life-limiting or life-threatening condition (n = 6), parents or guardians (n = 6), and bereaved family members (n = 9) in England and Wales between May 2021–September 2022. Interviews focused on what is important to the young people now and in the future. Constant comparative analysis methods were used to explore capabilities and factors influencing capability achievement (conversion factors). Seven capabilities were generated: Experience and enjoy; Independence; Freedom from physical suffering; Freedom from emotional suffering; Formal care and support; Control; Identity. Five conversion factors were generated: Access to care and support; Continuity and consistency in care and support; Communication with services; Coordination between services; and COVID-19. Findings can inform attribute development for a young person capability measure for use in economic evaluation capturing the broader outcomes of end-of-life care.