## 4 Discussion  
The methodology developed and presented in this study offers a systematic and efficient approach to selecting critical test scenarios for autonomous vehicles prior to their deployment in public traffic for testing or operational use. The key results demonstrate the practical applicability and relevance of a weighted cosine similarity-based filtering mechanism, combined with additional distance calculations, for scenario selection from a large database of over 1000 test cases. These results provide a foundation for improving safety validation and pre-deployment assessment of automated driving systems.  
The broader implications of the developed methodology extend to multiple stakeholders across the automotive industry. For TIC companies, the methodology provides a clear framework for pre-deployment assessments, offering an efficient way to evaluate readiness and safety before public road testing. Manufacturers, on the other hand, could integrate this process into iterative design and development cycles to describing ODD and OEDR.  
Moreover, the methodology demonstrates the value of leveraging existing protocols, standards, and regulations (e.g., EuroNCAP, UNECE, EU, ISO) to create standardized yet application-specific scenario catalogs. Such integration helps address regulatory gaps highlighted in recent discussions on the type approval of autonomous vehicles. For instance, by unifying terminology and parameters across diverse international testing frameworks, this study provides a foundation for comparative assessments, which is a noted challenge in the field.  
From a technical perspective, the capability of the filtering process to maintain relevance in selected cases while avoiding excessive redundancy ensures that critical safety gaps are addressed without overburdening simulation or testing resources. The application of Manhattan and Euclidean distances for filtering adds further refinement, enabling flexibility in the precision of scenario selection based on testing objectives. This capability could be particularly beneficial for public authorities (supported by TICs) as they scale up ADS-related type approval frameworks.  
Future developments could focus on expanding the test run database by incorporating additional standards, upcoming UNECE/EU regulations, and EuroNCAP protocols as they become available. By integrating these new standards and regulations, the methodology can be further refined to ensure an even more comprehensive and precise selection of test scenarios. Based on the continuous monitoring of the work of UN and EU working groups, as well as that of EuroNCAP and standardization bodies, we recommend updating the database on an annual basis.  
The primary objective of our work was to facilitate the definition of testing procedures related to type approval practices commonly used in Europe, as currently there is no harmonized procedure among Member States regarding the pre-registration examination of such vehicles. Consequently, our methodology is grounded in regulations that are also applied within the European context--though not exclusively--since most UN regulations are valid across multiple continents. Several non-European countries, such as Japan, Turkey, and Australia, also conduct type approval based on these frameworks. Therefore, the proposed methodology may potentially be applicable in these regions as well.