Non-statistical sampling in tests of controls: which statement is true?

• A. The auditor considers the same parameters when determining a non statistical sample size as when determining a statistical sample size.
• B. The calculated non-statistical sample should never be altered by the auditor.
• C. Non-statistical sampling plans provide a quantitative measure of sampling risk.
• D. The auditor's judgment in non-statistical sampling is guided by classical statistical sampling concepts.

Answer: (A)

In non-statistical sampling for tests of controls, planning still hinges on the same factors that drive sample size in statistical sampling—population size, the acceptable (tolerable) deviation rate, and the expected deviation rate. The difference is that, in nonstatistical sampling, the auditor relies on professional judgment rather than a formal formula to determine the exact sample size. This makes the approach flexible while still acknowledging how much deviation you can tolerate and how much you expect to find.

Why this is the best match: using the same planning factors means the auditor is comparing how much evidence is needed in relation to how big the population is and how risky the control is deemed to be, even if the calculation isn’t statistical. The other statements aren’t accurate: a non-statistical plan can be adjusted as work progresses, since professional judgment may lead to changing the sample size or scope; non-statistical sampling does not provide a quantitative measure of sampling risk; and non-statistical judgment is not guided by formal classical statistical concepts.