Do Key Audit Matters in Hong Kong and Mainland China Provide Incremental Information and Improve Audit Quality?

ABSTRACT

We examine the adoption of expanded audit reports that include key audit matters (KAMs) in Hong Kong (2016) and mainland China (2017). These jurisdictions are highly integrated and together constitute one of the largest economies to adopt the IAASB's reporting standards in a staggered fashion, while also differing in investor protection and legal enforcement. Using matched samples, pre‐post tests, and staggered difference‐in‐differences analyses with company fixed effects, we do not find compelling evidence that expanded audit reports affect market reactions or audit quality. These findings suggest a substantial gap between regulatory intent and implementation—on average, in these markets, KAMs do not appear to meet investors' demand for incremental information or to improve audit quality substantially. At the same time, our cross‐sectional evidence on KAM characteristics is more nuanced. A higher number of KAMs and the presence of novel or transaction‐specific KAMs are associated with stronger pricing of fundamentals, consistent with investors perceiving the related financial statements as better vetted. Yet a higher number of KAMs and novel KAMs are also associated with lower profitability persistence, consistent with these disclosures reflecting company risk and volatility. In contrast, industry‐common KAMs appear less relevant for valuation, consistent with investors discounting routine disclosures, even though they are associated with more persistent performance likely reflecting more stable industry conditions. Overall, our evidence suggests that mandating expanded audit reports alone may be of limited value, whereas better tailored KAM disclosures may still serve as signals of firm fundamentals and future performance.