Introduction: Next of kin involvement in cancer care services is complex, challenging and influenced by factors related to the organisation of the healthcare service, the resources of the next of kin, and the patient’s ability to cope with treatment and care. As the provision of cancer care services has changed from in-patient wards to out-patient clinics, next of kin involvement practice faces new challenges. As the roles of healthcare professionals and of patients are regulated by law, the formal expectations of the next of kin role are low in Norway. However, changes in the organisation of cancer care services bring a new perspective to the role of next of kin. The Ministry of Health Care Services requires healthcare services to acknowledge the next of kin’s need for relief, involvement, and contribution to patient care. Less is known about how to facilitate and adapt to these changes. Research confirms that next of kin involvement is a key factor in keeping a patient safe during the cancer care trajectory, but there has been little discussion of the best way to involve the next of kin. This PhD thesis addresses the lack of knowledge on next of kin role for quality and safety in hospital cancer care, and the need for methods and tools for next of kin’s systematic involvement in these services. Aim: The aims of the study were to explore the role of next of kin for quality and safety in hospital cancer care, and to develop a consensus- based guide for next of kin involvement in hospital cancer care. The objectives were: • to map next of kin involvement and methods used in two hospitals from the managers’ and healthcare professionals’ perspective, • to explore next of kin satisfaction with cancer care services and suggestion for next of kin involvement from the next of kin perspective, • to synthesise finding and explore topics and elements relevant for a next of kin involvement guide to support quality and safety in hospital cancer care. Methods: This study has utilised a mixed methods case study design, with a mixed methods convergent design at its core, including 1) a multiple embedded case study with managers and healthcare professionals (n=32) within cancer care departments in two University hospitals in Norway; 2) mapping of next of kin experiences with a questionnaire survey measuring their satisfaction with cancer care in the same two hospitals (n=238); and 3) conducting a modified Nominal group technique consensus process with a stakeholder groups (n=20) from both hospitals and next of kin representatives. The findings were integrated into a guide for next of kin involvement in hospital cancer care. Results: Paper I reports findings from a comparative multiple embedded case study of cancer departments in two Norwegian university hospitals. The aim was to explore how managers and healthcare professionals understand the role and contribution of next of kin in cancer care, and what methods they used to involve next of kin. Data collection consisted of analysis of national policy documents, and interviews with managers and healthcare professionals collected in 2016. Results showed that although healthcare professionals in both hospitals depended on next of kin collaboration throughout the care process, only a few systematic approaches to involvement were found. Managers and healthcare professionals in both hospitals insisted on a need for more guidance for next of kin involvement in hospital cancer care. This paper illuminates nine areas in which next of kin are important to quality and safety in cancer care: information, pain treatment, transitions, observations, motivation, emotional support, physical activity, rehabilitation, daily care, nutrition, palliative and terminal care. Paper II reports findings from the same comparative multiple embedded case study as in paper I. Data collection was the same, but the data was analysed by directed content analysis according to Hollnagel’s four potentials for resilient performance (respond, monitor, anticipate and learn). The results showed how next of kin are co-creators of resilient performance in hospitals. They complemented healthcare professionals in all four potentials for resilient performance. Paper III reports findings from a mixed methods convergent design study. Responses were collected from 238 next of kin between November 2016 and November 2017. The aim was to explore next of kin satisfaction with hospital cancer care and to use the results as a basis for improving quality and safety in hospital cancer care. The paper applied the 20-item FAMCARE scale as a survey instrument. Open-ended questions were used for qualitative analysis. The paper combined regression analysis, exploratory factor analysis and qualitative content analysis. Results showed that next of kin in both hospitals reported high satisfaction with care. In general, results showed a higher score on satisfaction with care (1.5,1.1-2.0), p < .001 (Wilcox signed test) than with involvement related items. This indicates a lack of systematic approaches and sound methods of involvement to improve satisfaction and service quality and safety. The largest difference between the case hospitals was found in item Q15 (“The way the family is included in treatment and care decisions”), with a 30% increased probability of being satisfied or very satisfied at hospital 1 (RR 1.3, 95% CI 1.1-1.7, p = .013). The synthesis of the mixed methods results of this study disclosed that next of kin should be acknowledged as an independent part in the healthcare team around the patient, and not merely as part of the patient’s role. Paper IV reports findings from a participatory consensus method based on a modified Nominal group technique process applied as a single one- day meeting with 20 stakeholder participants. The overarching research problem for the meeting was: What topics or elements should be included in a next of kin involvement guide to support quality and safety in hospital cancer care? This paper integrates agreed upon topics of next of kin-related challenges in hospital cancer care by presenting a guide development for use in clinical practice. The results showed key topics and elements designed for managers and healthcare professionals in the cancer care setting to guide improvement initiatives for quality and safety. The panel emphasised the importance of building systems for gathering experiences from next of kin, incorporate and use experiences for service improvement, tailor next of kin training, and support and create a culture that considers next of kin involvement as a prerequisite for sound patient care. The paper results in the Next of Kin Involvement Guide. The guide builds on the Organizing for Quality framework [1] and is adapted to the cancer care setting by integrating the key topics from the consensus process. Conclusion: The thesis has demonstrated that next of kin hold a vital role for quality and safety in the cancer care in the two case hospitals (e.g. transitions, palliative care, pain treatment, motivation, daily care). It also disclosed that hospital cancer care lacked systematic next of kin involvement in the organisation of healthcare services. In addition, tools and guides for sound next of kin involvement were missing. By identifying suggested methods for involvement (e.g. system improvement, user surveys, one appointed healthcare professional for the next of kin, closer interaction with support bodies) from the managers’, healthcare professionals’, and next of kin’ perspectives, and by integrating these into the Next of Kin Involvement Guide (Figure 5.), the thesis contributes with a requested tool that has the potential to support managers’ and healthcare professionals’ future working on quality and safety in hospital cancer care.