20 Chapter 1 The second section of the thesis focusses on the assessment of the performance of robotic surgeons. In this section research questions will be answered in multiple chapters (figure 1). Chapter 6 focusses on research question 6 ‘Is it possible to find differences between surgeries that are relevant to the outcome of the intervention by analysing video material?’, it describes which aspects of the RARP are of influence in the origin of postoperative outcome according to the opinion of RARP experts. The results of this Delphi process were used to develop an assessment template which can be used in the technical skills assessment of RARP surgery. Chapter 7 describes the research protocol for a prospective observational multicenter study concerning non-technical skills in robot assisted radical cystectomy versus open radical cystectomy. This study was designed to evaluate the differences in NTS between open and robot assisted surgery. In Chapter 8 we review the opinions of surgeons who perform Robot Assisted Radical Prostatectomy on the influence of postoperative results analysis and surgical video review. This study gives insight into the use of surgical video review in daily practice which provides insight for further research. The third section of the thesis focusses on the relation between a surgeon’s performance and a patient’s postoperative outcomes. In this section research questions will be answered in multiple chapters (figure 1). In Chapter 9 and Chapter 10 research question 4 ‘Which technical and non-technical skills factors in robot assisted surgery (competence, teamwork, dedicated OR team, patient factors, environmental factors) influence clinical and patient-related outcomes?’, research question 5 ‘Is video analysis a valid measuring tool to assess the competence of surgeons?’ and research question 6 ‘Is it possible to find differences between surgeries that are relevant to the outcome of the intervention by analysing video material?’ are answered in order to identify which factors of RARP using different methods of surgical video assessment influence postoperative outcome. Different methods of surgical video analysis, including assessment by expert surgeons, were used to identify differences in surgical skill and relating them to the postoperative outcome of the patient.