Sampling Method
MUS is standard for substantive overstatement testing. Classical is used when items are similar in size or when testing for understatement.
↳ ISA 530.A4 — items are selected proportional to their monetary value. Larger items have a higher probability of selection. Standard for overstatement testing.
Confidence Level
Reflects the assessed risk of material misstatement. Higher confidence = larger sample.
↳ Risk of incorrect acceptance: 10%. Confidence factor (CF): 2.31.
Population & Materiality
Enter the total monetary value of the population being sampled and the materiality thresholds from your planning.
Total monetary value of the account or class of transactions
Typically performance materiality or a fraction of it
Prior year misstatements or current estimate. Leave blank or enter 0 if none.
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Sampling Considerations for Non-Profit
Non-profit audits involve unique sampling challenges: donation income may be difficult to verify with traditional confirmation techniques, grant-funded programmes require compliance testing against specific conditions, and restricted funds must be tested for proper segregation and usage. The populations are often a mix of many small donations and fewer large grants or bequests.
Sampling focus: Non-Profit
Donation income sampling should be stratified by source type and size — large institutional grants versus small individual donations have fundamentally different audit approaches. For grant expenditure, attribute sampling tests whether spending complies with donor restrictions. Restricted fund testing verifies that funds are used in accordance with donor-imposed conditions.
Key sampling considerations
Donation income from individuals is inherently difficult to verify — for small cash donations, focus on testing internal controls over collection and recording rather than substantive sampling of individual gifts. Large grants and institutional donations can typically be tested individually — focus sampling efforts on the population of medium-sized donations where neither 100% testing nor pure reliance on controls is practical. Grant compliance testing should sample expenditure items charged to each restricted fund to verify they meet the grant conditions — non-compliance can trigger repayment obligations. Volunteer time and in-kind donations, if recognised, require separate sampling to verify the valuation methodology and the basis for the fair value estimate. Fundraising expenditure ratios are sensitive for non-profits — sample expenditure classifications to verify that programme costs are not misclassified as fundraising or vice versa.
ISA 530.5 — Audit sampling means applying audit procedures to less than 100% of items within a population so that all sampling units have a chance of selection.
ISA 530.A4 — MUS uses monetary units as the sampling unit, giving each monetary unit an equal probability of selection.
ISA 530.A11 — Sample size is affected by the tolerable misstatement, expected misstatement, and the required level of confidence.