According to IIA Standards, acceptable practices for testing conformance through a quality assurance review include conducting a self-assessment with independent validation (2) and arranging for reciprocal peer review with another CAE (4). These methods provide a cost-effective and practical approach to ensuring compliance with professional standards, especially for small internal audit activities. Using an external service provider (1) and arranging for a review by qualified employees outside of the IAA (3) are also valid, but self-assessment with independent validation and peer review are specifically highlighted for smaller IAAs. References: IIA Standard 1312 - External Assessments, IIA Practice Guide - Quality Assurance and Improvement Program