지속가능성 공시품질의 결정요인

[Purpose]This study aims to investigate the determinants of sustainability disclosure quality, with a particular focus on how internal governance structures, ownership characteristics, and external assurance mechanisms affect the credibility and usefulness of ESG－related disclosures. [Methods]Using panel data from 55 non－financial firms in Korea that voluntarily issued sustainability reports between 2016 and 2022, we construct a disclosure quality index along two dimensions—content and form—based on established scoring frameworks. Multiple regression and Heckman two－stage models are employed to address potential endogeneity. [Findings]The results reveal that CEO power negatively impacts both content and format aspects of sustainability disclosure quality. Conversely, the presence of an ESG committee, board independence, and higher foreign investor ownership positively contribute to disclosure quality. External assurance provided by third parties consistently enhances sustainability disclosure quality across both dimensions. Furthermore, the interaction between CEO power and external assurance demonstrates that firms with weaker CEO power and third－party assurance exhibit significant improvements in disclosure quality, particularly in terms of format. These findings were robust to a Heckman two－stage analysis, further addressing endogeneity issues. [Implications]This study is one of the first to examine the factors influencing sustainability report disclosure quality from the perspectives of corporate governance, ownership structure, and external assurance. The findings provide empirical evidence for mechanisms that enhance the credibility of sustainability reporting. From both academic and practical standpoints, the results underscore the critical role of third－party assurance in improving the quality of sustainability disclosures.