學術界和監管者普遍關注審計客戶重要性對審計品質的影響。然而在度量客戶重要性時，研究者通常以來自所有上市客戶（而非全部客戶）的經濟利益作為客戶重要性基數的替代指標。來自中國註冊會計師行業組織的統計資料為我們考察上述度量偏差的潛在影響提供了機會。以客戶重要性與客戶應計盈餘管理間關係為檢驗情境，本文證據顯示，是否完整度量事務所的業務收入基數對客戶重要性經濟後果的估計具有明顯影響；同時該項度量偏差對理解事務所不同分部（office）在客戶重要性經濟後果上的潛在差異也具有明顯影響。

The impact of client importance on audit quality has long been attracting academic and regulatory attention. When measuring client importance, however, researchers usually use the economic benefits from all listed clients (rather than all clients) as a proxy for the revenue base of client importance. Taking advantage of a unique set of data from the Chinese Institute of Certified Public Accountants (CICPA), this study examines the potential impact of such measurement bias on empirical findings. Using the association between client importance and accrual-based earnings management as the test scenario, our evidence shows that when evaluating the economic consequences of client importance, the use of a complete client base in measuring client importance leads to a discernibly different interpretation to that produced using an incomplete client base. Moreover, the measurement bias also has a discernible impact on the interpretation of empirical results at the audit firm office level.