Most existing studies on EDI effects have been predominantly one-dimensional, fragmented, and superficial; however, some prior studies have theoretically argued that EDI effects are interrelated in a hierarchical structure. Nevertheless, empirical studies that have verified the causal relationships among EDI effect factors are difficult to find. Therefore, this study conducted empirical research to support the theoretical explanations from prior studies, analyzing the interrelationships among EDI effect constituent factors in a multi-dimensional manner to identify causal relationships hierarchically and to develop a causal model of EDI effect constituent factors. The main contents of this study are as follows: First, EDI effect items necessary for developing measurement instruments were derived through a literature review on flat and hierarchical EDI effects, and data were collected from EDI-using firms and analyzed to identify EDI effect constituent factors. Second, the multi-dimensional causal relationships among the five effect constituent factors revealed through data analysis were represented in a path diagram to propose a causal model of EDI effect constituent factors. Third, the proposed causal model based on prior research on EDI effects was empirically verified through covariance structure analysis using LISREL, and the results were interpreted to present the study's implications and limitations. The research results can be summarized as follows: First, hierarchical structures with interrelationships were found among time reduction factors and cost reduction factors, information quality factors and operational efficiency improvement factors, cost reduction factors and competitive advantage factors, and operational efficiency factors and competitive advantage factors. Second, no significant causal relationship was found between time reduction factors and operational efficiency improvement factors. Third, information quality factors and cost reduction factors were found to have a negative causal relationship. Fourth, time reduction factors and information quality factors were verified to have causal relationships with cost reduction factors and operational efficiency factors, and cost reduction factors and operational efficiency factors were verified to have causal relationships with competitive advantage factors. The goodness-of-fit evaluation of the three-layered causal model proposed in this study confirmed that it is an adequate model as an exploratory model.