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Audit sample size (attribute sampling)
Find how many items to test for a control so that a clean or near-clean result supports your conclusion.
Governance, risk & complianceHow it's worked out
- Smallest n where P(deviations ≤ k | n, tolerable rate) ≤ 1 − confidence (binomial). Finite population adjustment n ÷ (1 + (n − 1) ÷ N)
- Random selection; deviations independent
NoteIf you find more deviations than you planned to accept, the control fails at this confidence. For very small populations, many audit methodologies test a fixed number by control frequency instead.
Source: AICPA Audit Guide: Audit Sampling (attribute sampling tables)
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