회계법인의 특성이 감사법인의 감사품질에 미치는 영향: 외감법 규정을 중심으로

[Purpose]This study examines whether the scoring system of the mandatory auditor designation regime, introduced after the enforcement of the New Act on External Audit of Stock Companies in Korea, appropriately reflects audit quality. Furthermore, it investigates how audit firm characteristics influence audit quality. While prior research has largely focused on single indicators such as Big4 affiliation or audit hours, this study emphasizes the institutional scoring variables as well as internal resource structure variables highlighted in prior studies, with particular attention to the proportion of quality control personnel expenses (QualityCost). By doing so, the study aims to assess whether the current scoring system sufficiently captures the key determinants of audit quality. [Methodology]Using a sample of Korean listed firms from 2019 to 2023, we employ firm－ and year－fixed effects models to examine the association between the auditor designation scoring variables, audit firm internal characteristics, and client firms’ audit quality, measured by discretionary accruals and real earnings management. [Findings]The empirical results show that most scoring variables are not significantly associated with audit quality. However, the proportion of quality control personnel expenses is found to significantly improve audit quality. This finding suggests that internal quality control capability, rather than audit firm size or Big4 affiliation, is the critical driver of audit quality. Moreover, the effect is particularly pronounced for small－ and medium－sized firms with total assets below KRW 2 trillion, highlighting the limitation of applying a uniform scoring system across different firm groups. [Implications]First, this study provides empirical evidence that the current scoring system of the mandatory auditor designation regime does not fully capture audit quality, emphasizing the need to strengthen internal resource allocation indicators such as quality control personnel expenses in future regulatory reforms. Second, by considering firm heterogeneity based on asset size, the study shows that the positive effect of quality control investment is more pronounced for firms with assets below KRW 2 trillion. This finding offers policy implications for regulators to design mechanisms that incentivize audit firms to enhance quality control resources when auditing small－ and medium－sized enterprises.