Supplier Selection Problem Using Combined Approaches of Neutrosophic-Based Quality Function Deployment and EDAS

The evaluation and selection of suppliers is a crucial issue in supply chain management. This problem has grown increasingly uncertain due to the influence of imprecise parameters, and various tools have been proposed for weighting criteria and evaluating supplier scores for each criterion. Neutrosophic numbers, a modern tool for handling uncertainty, ambiguity, and inconsistency, are introduced to tackle such challenges. As the most comprehensive form of non-classical logic after fuzzy and intuitionistic fuzzy logic, Neutrosophic logic assigns degrees of membership, non-membership, and hesitation independently between zero and one. In this research, the quality function deployment (QFD) technique is developed in a Neutrosophic environment to identify and weigh supplier evaluation criteria. Additionally, the Neutrosophic EDAS approach is proposed for selecting top suppliers. A numerical study of the pharmaceutical industry demonstrates that geographical location and supplier experience are the two most critical criteria, and the second supplier is chosen as the best.