Consumers’ ethical beliefs, ethical sensitivity and multi-dimensional ethical consumption behavior: a multi-method investigation using PLS-SEM, NCA, and fsQCA

Purpose This study aims to address the limited insights in existing literature regarding the complex interplay between ethical beliefs (idealism, relativism), ethical sensitivity and multi-dimensional ethical consumption behavior (ECB), particularly within the context of developing countries such as Vietnam. Using Self-Identity Theory and Hunt–Vitell Theory of Ethics, the research seeks to provide a comprehensive understanding of these relationships among Vietnamese consumers by using an integrated analytical approach. Design/methodology/approach This research used a quantitative method, collecting data via a survey from 416 participants in Vietnam. The data were subsequently analyzed using an integrated three-stage procedure: Partial Least Squares Structural Equation Modeling (PLS-SEM) to assess net effects and mediation; Fuzzy Set Qualitative Comparative Analysis (fsQCA) to uncover sufficient configurations; and Necessary Condition Analysis (NCA) to identify essential prerequisites and bottlenecks. Findings The results show that ethical sensitivity plays a critical mediating role in translating consumers’ ethical beliefs into ethical consumption behavior. The PLS-SEM analysis confirms that both idealism and relativism positively influence ethical sensitivity, which in turn significantly promotes multidimensional ethical consumption behavior. Complementing these symmetric findings, fsQCA reveals multiple configurational pathways leading to high ethical consumption behavior, demonstrating that different combinations of ethical beliefs and ethical sensitivity can produce similar outcomes. Notably, the analysis highlights the asymmetric and context-dependent role of relativism across configurations. In addition, NCA identifies idealism, relativism and particularly ethical sensitivity as necessary conditions for achieving high levels of ethical consumption behavior, with ethical sensitivity showing the strongest necessity effect. Originality/value This study advances ethical consumption research by theoretically integrating the Hunt–Vitell Theory of Ethics and Self-Identity Theory to explain how ethical beliefs translate into ethical consumption behavior through ethical sensitivity as a key psychological mechanism. By bridging moral evaluation and identity-driven behavior, the study provides a more comprehensive understanding of how consumers’ ethical beliefs are transformed into ethical consumption practices. Methodologically, the research adopts a multi-method analytical framework that combines PLS-SEM, fsQCA and NCA, enabling the identification of both sufficient configurations and necessary conditions underlying ethical consumption behavior in a developing-country context.