A systematic process is used for both assessments and audits.  Both are applied as a management tool as oppose to a technical-review tool.  Outcome of both is a report. They both often use similar methods and techniques to perform their appraisal.

Note:  This article focuses on

some of the similarities and distinguishing factors between

the terms assessment and audit when expressed in the software industry.

Auditor/assessor style (e.g., impartial, collaborative) is dependent on the appraisal-customer (internal vs external) and, the appraisal's purpose and potential impact/risks.

Audit/assessment duration and type of interaction (group vs 1-on-1) depends on purpose, scope and type of appraisal.

Note:  The differences shown above are typical -- self-triggered assessments/audits may be

any combination of that shown or special cases such as that for dry-run audits.