本文以2016、2017年揭露關鍵查核事項（key audit matters，簡稱KAM）的台灣上市櫃公司為樣本，檢視KAM揭露與審計品質及審計報告時效性之關聯性。KAM揭露係以會計師於查核報告中揭露的KAM項目數以及對KAM之說明字數加以衡量，審計品質與審計報告時效性分別以裁決性應計數與審計報告延遲衡量。實證結果發現KAM揭露項目數及說明字數皆與裁決性應計數負相關，表示會計師對KAM揭露項目數愈多及對其說明愈詳細，愈有利於促使受查客戶提列較低的裁決性應計數，隱含KAM之揭露有助於抑制受查客戶調高報導盈餘之行為。額外分析亦發現KAM之項目數及其字數與裁決性流動應計數及實質盈餘管理呈負相關。此外，本研究發現KAM揭露項目數及說明字數愈多將延遲發布審計報告。

Using data from Taiwanese listing companies whose auditors disclose key audit matters (KAM) in audit reports of 2016 and 2017, this study examines the association between KAM disclosures, audit quality, and audit report timeliness. The extent of KAM disclosures is determined by the number of key audit matters disclosed and the number of words auditors use to explain key audit matters. Audit quality and audit report timeliness are proxied by discretionary accruals and audit report lag, respectively. The empirical results show that KAM disclosures are inversely correlated with discretionary accruals, suggesting that the more key audit matters disclosed and the more detailed explanations provided by auditors, the lower the client's discretionary accruals. These results indicate that disclosing KAMs helps auditors constrain clients' increasing reported earnings behaviors. Moreover, disclosing KAMs delay the issuance of audit reports.