Frost J, Wingham J, Britten N, et al. - Through a mixed-methods process assessment parallel to a randomized, controlled trial using data from the intervention group, researchers identified and assessed change processes describing the impact of the intervention, taking account of reach, amount of intervention received, delivery fidelity, and patient and caregiver perspectives. Intervention session participation with facilitators was high. Fidelity scores were suggestive of the sufficient quality of intervention delivery, but indicated scope for improvement in several areas. On matching the intervention implementation to the concerns, beliefs, and goals of individuals, intervention efficiency was contingent. When shared meaning was ascertained, behavior variation was sustained. Variations in health-related quality of life was also influenced by respondents’ comorbidities, socio-economic circumstances, and existing networks of support. Hence, the fundamental components of complex interventions could be better identified, cross-examined, and examined by combining longitudinal mixed methods data, which, in turn, could maximize the clinical application of research findings and improve the range of multidisciplinary and multisite teams to implement the intervention.