4.3 Substantive Procedures and Audit Evidence
Key Takeaways
- The 2026 AUD blueprint allocates 30-40% to Area III, Performing Further Procedures and Obtaining Evidence, the largest AUD content area.
- Sufficiency is the quantity of evidence; appropriateness is the quality of evidence, judged by relevance and reliability.
- External confirmations, auditor recalculations, reperformance, and original external documents are generally more reliable than unsupported internal representations.
- Substantive procedures comprise tests of details and substantive analytical procedures, and the procedure must fit the assertion being tested.
- Written representations are required in an audit but never substitute for evidence that should be available from other sources.
Evidence Is the Core of AUD
The 2026 AUD blueprint gives Area III, Performing Further Procedures and Obtaining Evidence, the largest allocation at 30-40%. This area tests whether a candidate can choose the right procedure, evaluate the evidence it produces, analyze exceptions, and conclude whether the planned objective was achieved. Because it overlaps heavily with the seven task-based simulations, it is the highest-yield section in the chapter.
Sufficient appropriate audit evidence has two halves. Sufficiency is quantity: how much evidence is needed, which rises with assessed risk and falls with evidence quality. Appropriateness is quality: whether the evidence is both relevant (it addresses the specific assertion) and reliable (it can be trusted). Higher assessed risk of material misstatement usually demands more evidence, more persuasive evidence, or both.
Reliability Patterns
| Evidence source or method | Usually stronger when... | Watch the limitation |
|---|---|---|
| External confirmation | It comes directly from an independent party | Nonresponses and exceptions need follow-up |
| Recalculation | The auditor independently checks math or formulas | It does not prove the underlying data is valid |
| Reperformance | The auditor independently executes the control or procedure | Scope must match the control objective |
| Inspection | Original external documents are available | Internal documents can be less reliable |
| Inquiry | It explains facts or motives | It rarely provides enough evidence alone |
| Analytical procedures | Relationships are predictable and data is reliable | Unexpected differences must be investigated |
Reliability is never automatic. A bank confirmation is strong for cash existence but may not establish restriction or classification without added detail. A management-prepared schedule may be useful, but the auditor must verify its completeness, accuracy, authenticity, and susceptibility to bias before relying on it. Evidence from sources independent of the entity and obtained directly by the auditor ranks highest. A general reliability hierarchy: directly obtained evidence beats indirectly obtained; original documents beat photocopies or scans; documentary evidence beats oral; and externally generated evidence beats internally generated.
The exam rewards candidates who can rank two procedures on these dimensions rather than simply labeling any procedure "reliable."
Tests of Details and Substantive Analytics
Tests of details examine individual transactions, balances, or documents: confirming receivables, inspecting a debt agreement, tracing vendor invoices to recorded accruals, or agreeing subsequent cash receipts to customer balances. Substantive analytical procedures (SAPs) use expected relationships to support an assertion. SAPs work best when the relationship is predictable, the data is reliable, and the auditor can build a precise expectation. Rent under a fixed lease is a good candidate; revenue for a volatile new product with shifting prices is a poor one unless the expectation is carefully modeled.
Procedure Selection by Assertion
| Assertion need | Better procedure direction |
|---|---|
| Existence of receivables | Confirm balances or test subsequent cash receipts |
| Completeness of liabilities | Search for unrecorded liabilities: examine subsequent disbursements and unmatched receiving reports |
| Valuation of the allowance for credit losses | Test aging data, historical loss rates, current conditions, and key assumptions |
| Cutoff of revenue | Inspect shipping terms and transactions just before and after year-end |
| Rights and obligations | Inspect contracts, title documents, or custodian confirmations |
The exam frequently asks for the best next procedure after an exception. If a positive receivable confirmation is not returned, the auditor performs alternative procedures, such as inspecting subsequent collections, sales invoices, and shipping documents. The auditor does not assume the balance is valid because the customer stayed silent, and does not quietly drop the item from the sample.
Special Evidence Areas
Area III also covers estimates, investments in securities, inventory held by others, litigation and claims, going concern, single-audit compliance testing, evaluation of misstatements, internal control deficiencies, written representations, and subsequent events. These topics test judgment:
- Litigation: inquiry of management alone is not enough; the auditor reviews board minutes, sends an attorney letter (a letter of audit inquiry to legal counsel), and considers other corroborating evidence.
- Inventory: observation of the count supports existence and condition, but valuation still needs pricing tests and obsolescence analysis.
- Subsequent events: events through the date of the auditor's report may require adjustment (Type 1, conditions existing at the balance-sheet date) or disclosure (Type 2, conditions arising after).
- Going concern: the auditor evaluates whether substantial doubt exists for a reasonable period, generally one year from the date the financial statements are issued.
Written representations from management are required and document management's acknowledgments, but they are not a shortcut around missing evidence. If persuasive evidence should exist and management offers only a representation, the auditor considers whether a scope limitation or heightened fraud risk is present.
Exam Focus
The best AUD evidence answer is specific to the assertion, independent where possible, and responsive to the assessed risk. Generic procedures lose to procedures that directly test the identified account, population, period, and misstatement risk. When two answers both "work," pick the one that produces more reliable evidence about the exact assertion in question.
Management gives the auditor an AI-generated sales-trend report and asks the auditor to use it as evidence for revenue completeness. What should the auditor do before relying on the report?
A positive confirmation request for a material receivable is not returned. Which response is most appropriate?