An internal audit activity maintains a quality assurance and improvement program that includes annual self-assessments...

According to the IIA Standards, an internal audit activity must have an external assessment conducted at least once every five years by a qualified, independent reviewer or review team from outside the organization. The validation by an external team ensures that the internal audit activity ' s self-assessments and quality assurance practices meet the required standards.

IIA Standard 1312 (External Assessments) and IIA Standard 1320 (Reporting on the Quality Assurance and Improvement Program) provide detailed guidelines for this process.