In today's world, addressing multi-criteria decision problems presents a considerable challenge due to their inherent complexity. Decision-makers face diverse and often conflicting factors that exceed their analytical capabilities and complicate the identification of the best solutions. Within this intricate field, Multi-Criteria Decision Analysis (MCDA) serves as an important decision support tool. The complex nature of these problems introduces numerous variables that influence the final choice. This complexity requires sensitivity analysis as an indispensable part of the assessment process. It allows for an examination of how changes in input data can affect the outcomes, providing valuable insights into the stability and reliability of the decision-making process. Based on the state-of-the-art, this study identifies a gap in sensitivity analysis, particularly in assessing the impact of modifications to the decision matrix. Although one-at-a-time (OAT) modification is efficient, simultaneously changing multiple elements provides nuanced insights into decision-matrix interdependencies. Therefore, this research introduces a novel sensitivity analysis method, the COMprehensive Sensitivity Analysis Method (COMSAM), which systematically modifies multiple values within the decision matrix. The COMSAM allows for a detailed problem space exploration, providing insights into alterations across criteria values. Furthermore, the method represents the preferences obtained from the evaluations as interval numbers, offering decision makers additional knowledge about the uncertainty of the analyzed problem. This study advances the field of sensitivity analysis, providing a new perspective on changes in multiple values' simultaneous influence on the robustness of the MCDA result. • COMSAM: A new method for comprehensive sensitivity analysis for multi-criteria problems. • Enhance the applicability of MCDA by providing decision-makers with additional knowledge about the problem. • Develop unexplored areas in a sensitivity analysis by multiple simultaneous modifications in the decision matrix. [ABSTRACT FROM AUTHOR]