According to IIA guidance, elements of evaluation reflect a valid principle for the internal audit activity to rely on the work of internal or external assurance providers. This principle involves assessing the competence, objectivity, and performance of the assurance providers to ensure their work can be relied upon. Proper evaluation helps internal auditors determine the extent to which they can use the work of others in forming their conclusions.
Reference:
IIA Standards: 2050 - Coordination and Reliance
IIA Practice Guide: Reliance by Internal Audit on Other Assurance Providers