178 Chapter 6 was reviewed by all panel members in order to give them the opportunity to refine and clarify the assessment instrument. One item, “Wound closure and specimen removal”, was not included in the PROTEST assessment instrument, because this step is not recorded on surgical videos. When comparing the results of the current Delphi study to existing assessment instruments15,24,25, the developed PROTEST assessment instrument shows a combination of subjective surgical skills assessment and objective metrics of procedural steps and events. The developed PROTEST assessment instrument is different from the GEARS assessment instrument where the focus lies solely on the subjective scoring of 5 technical domains of surgical skill, with no objective measurements.23 The GERT assessment instrument comparable to the PROTEST assessment instrument as it focusses on different features of the surgery (i.e. clipping, suturing, use of the retractors and use of suction), but it only gives feedback on possible errors whilst performing this feature, there is no room to score subjective surgical skills.24 The PACE assessment instrument is similar to the GERT assessment instrument as it evaluates specific steps of the RARP procedure, similar to the PROTEST assessment instrument, but only gives feedback based on errors whilst performing these steps and there is no room for subjective surgical skill analysis.15 Implications of study findings for clinical practice and research This Delphi procedure resulted in an overview of possible origins of complications after RARP and in a new assessment instrument that can be used to objectively assess a surgeon’s skills. The PROTEST assessment instrument gives detailed insight into the proficiency of the surgeon on each of the individual surgical steps of the RARP. It combines the answers to two general subjective questions with multiple objective measurements in order to provide detailed feedback to the surgeon. Future studies should explore whether the factors identified in this Delphi process are indeed causally related to postoperative complications and whether video assessments by means of the PROTEST instrument can help in the training of novice surgeons and improving the skills of RARP surgeons. Limitations A limitation of this study is that we consulted all the urologists specialized in RARP who are registered in the Netherlands. Future studies with larger panels and international participants might add other factors that could contribute to complications after RARP.