Background The recurrence of sentinel events (SEs) is a persistent problem worldwide, despite repeated analyses and recommendations formulated to prevent recurrence. Research suggests this is partly attributable to the quality of the recommendations, and determining if a recommendation will be effective is not yet covered by an adequate guideline. Our objectives were to (1) develop and validate criteria for high-quality recommendations, and (2) evaluate recommendations using the criteria developed. Methods (1) Criteria were developed by experts using the bowtie method. Medical doctors then determined if the recommendations of Dutch in-hospital SE analysis reports met the criteria, after which interobserver variability was tested. (2) Researchers determined which recommendations of Dutch perioperative SE analysis reports produced from 2017 to 2018 met the criteria. Results The criteria were: (1) a recommendation needs to be well defined and clear, (2) it needs to specifically describe the intended changes, and (3) it needs to describe how it will reduce the risk or limit the consequences of a similar SE. Validation of criteria showed substantial interobserver agreement. The SE analysis reports (n=115) contained 442 recommendations, of which 64% failed to meet all criteria, and 28% of reports did not contain a single recommendation that met the criteria. Conclusion We developed and validated criteria for high-quality recommendations. The majority of recommendations did not meet our criteria. It was disconcerting to find that over a quarter of the investigations did not produce a single recommendation that met the criteria, not even in SEs with a fatal outcome. Healthcare providers have an obligation to prevent SEs, and certainly their recurrence. We anticipate that using these criteria to determine the potential of recommendations will aid in this endeavour. @en