In this scenario, the internal auditor performed a test of controls on the accounts receivable ledger and found that the error rate was within management's expectations. Since the audit focused on the accounts receivable controls, the conclusion should be specific to the scope of the engagement. The auditor can provide positive assurance about the effectiveness of the controls over the recording of transactions in the accounts receivable ledger, as the evidence gathered supports this conclusion.
IIA Reference:
IIA Standard 2410: Criteria for Communicating states that communications must include the engagement's objectives and scope as well as applicable conclusions, recommendations, and action plans. Since the engagement was focused on accounts receivable, the assurance provided should relate specifically to the controls in that area.
The Practice Guide on Communicating Results emphasizes that conclusions and assurance should be directly related to the scope of the engagement and the evidence obtained.