The best approach to optimize resources when both internal and external audit teams are reviewing the same IT general controls area is to leverage the work performed by external audit for the internal audit testing. This can avoid duplication of efforts, reduce audit costs and enhance coordination between the audit teams. The internal audit team should evaluate the quality and reliability of the external audit work before relying on it.
Ensuring both the internal and external auditors perform the work simultaneously is not an efficient use of resources, as it would create redundancy and possible interference. Requesting that the external audit team leverage the internal audit work may not be feasible or acceptable, as the external audit team may have different objectives, standards and independence requirements. Rolling forward the general controls audit to the subsequent audit year is not a good practice, as it would delay the identification and remediation of any control weaknesses in a high-risk area. References: ISACA, CISA Review Manual, 27th Edition, 2018, page
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