Risk management of the vaccine supply chain: Interactions of risk factors and control strategies

Existing research on vaccine supply chain (VSC) risk management often focuses on transportation or production stages or simply lists risk factors, lacking comprehensive identification and exploration of their interrelationships. This paper aims to address this gap by identifying and systematically analyzing risk factors in the single-dose COVID-19 VSC, emphasizing their structural hierarchy, interrelationships, and relative importance. The study summarizes VSC risk factors using the Supply Chain Operations Reference (SCOR) model. It innovatively combines Total Interpretive Structural Modeling (TISM) with Cross-Impact Matrix Multiplication Applied to Classification (MICMAC) and complex network theory. This yields the TISM hierarchical model, a driving power-dependence matrix, and comprehensive importance values for all risk factors. The TISM model reveals that risk awareness level, human resource level, and supplier selection capability are at the base level, functioning as fundamental factors with deep regulatory effects. The driving power-dependence matrix indicates that risk awareness level, human resource level, and supplier selection capability are independent factors characterized by high driving power and low dependence. The comprehensive importance calculations rank delivery integrity and product quality level at the top. Furthermore, sensitivity analysis is also performed to check the robustness of the proposed model. Understanding the relationships between risk factors, elucidating their logical explanations, and identifying key risk factors enable stakeholders to better manage risks and stabilize VSC operations.