Abstract
Purpose In response to the users of financial statements' need for better communication value from audit reports, auditors are required to expand the format and content of their reports. This paper aims to investigate the heterogeneity of key audit matters (KAM) for big4 audit firms. Design/methodology/approach Using a pool of 273 year-observations from the Omani capital market for the period 2016-2019, a quantile regression approach is adopted to achieve this purpose because it can provide a broader picture of this heterogeneity. Findings The results indicate that all types of big4 audit firms are associated with lower numbers of KAM. However, each big4 audit firm reports these KAM differently. Also, the results indicate heterogeneity in the number of KAM among the partners of each firm. Specifically, partners in some big4 audit firms show a significant association with fewer KAM while others are insignificant. Some partners of Ernst and Young show a positive association with a higher number of KAM. Overall, the results confirm the heterogeneity among auditors in styling their KAM disclosure. Originality/value There are crucial implications for various policymakers. This paper is the first to analyse KAM aspects at the partner level and use quantile regression to detect the effect of audit firms on KAM.