AUD: Audit Evidence and Procedures

Audit evidence is the foundation upon which auditors form their opinion on financial statements. Without it, an audit opinion is meaningless. For CPA candidates, mastering what constitutes audit evidence, how to obtain it, and how to evaluate its quality is not just an exam topic; it is the core skill of the auditing profession, essential for protecting the public interest and ensuring the credibility of financial reporting.

What is Audit Evidence?

Audit evidence refers to all the information used by the auditor in arriving at the conclusions on which the audit opinion is based. It includes accounting records underlying the financial statements and corroborating information from other sources. The entire audit process is designed to gather and evaluate this evidence. The nature and timing of audit procedures are directly linked to the financial statement assertions management makes. These assertions are classified as follows:

• Assertions about Classes of Transactions and Events: Occurrence, Completeness, Accuracy, Cutoff, Classification.
• Assertions about Account Balances at Period End: Existence, Rights and Obligations, Completeness, Valuation and Allocation.
• Assertions about Presentation and Disclosure: Occurrence and Rights and Obligations, Completeness, Classification and Understandability, Accuracy and Valuation.

Your audit procedures are selected to test these specific assertions. For example, to test the existence of inventory, you would perform physical inspection. To test the completeness of accounts payable, you would search for unrecorded liabilities.

The Cornerstones: Sufficient Appropriate Audit Evidence

The auditor’s objective is to obtain sufficient appropriate audit evidence to reduce audit risk to an acceptably low level. This standard has two critical, interrelated components:

1. Sufficiency refers to the quantity of audit evidence. It is a measure of how much evidence is obtained. Sufficiency is influenced by the auditor’s assessment of audit risk (higher risk requires more evidence) and the quality of the evidence itself (higher-quality evidence may require a smaller sample size).

1. Appropriateness refers to the quality of audit evidence—its relevance and reliability in providing support for the conclusions drawn. Relevance relates to the assertion being tested, while reliability is influenced by several key factors:

• Source: Evidence obtained directly by the auditor (e.g., physical observation) is more reliable than evidence obtained indirectly or from outside sources.
• Nature: Documentary evidence (especially original documents) is more reliable than oral representations.
• Internal Controls: Evidence generated from a well-designed and effectively operating internal control system is more reliable than evidence generated from a weak system.

In practice, sufficiency and appropriateness are inversely related. Higher-quality (more appropriate) evidence generally means you need less of it (lower sufficiency) to reach a conclusion. Conversely, if evidence is less reliable, you must gather more of it.

Types of Audit Procedures for Obtaining Evidence

Audit evidence is gathered through specific audit procedures. The CPA exam requires you to know not just what these are, but when and why to apply them. They are the tools in your audit toolkit.

• Inspection: Examining records or documents (internal or external) or physically examining an asset. Inspecting a signed lease agreement tests rights and obligations, while inspecting inventory tests existence.
• Observation: Looking at a process or procedure being performed by others. Observing the client’s inventory count provides evidence about the existence assertion and the client’s counting procedures. A key limitation is that observation is only pertinent at the point in time it occurs.
• Inquiry: Seeking information from knowledgeable persons inside or outside the entity. Inquiries range from formal written inquiries to informal oral questions. Crucially, inquiry alone is not sufficient; it must be corroborated with other evidence due to its inherent lack of reliability.
• Confirmation: The process of obtaining a direct written response from a third party verifying the accuracy of information. Confirmations are highly reliable external evidence. Common examples include bank confirmations (existence, rights) and accounts receivable confirmations (existence, valuation).
• Recalculation: Checking the mathematical accuracy of documents or records. Re-performing a client’s depreciation schedule or an inventory extension is an example of recalculation, testing the accuracy and valuation assertions.
• Reperformance: The auditor’s independent execution of procedures or controls that were originally performed by the client. For example, if the client has a control where a manager approves purchase orders, reperformance would involve the auditor tracing a sample of purchase orders to verify the manager’s signature was present.
• Analytical Procedures: Evaluations of financial information through analysis of plausible relationships among both financial and non-financial data. They are used in planning (risk assessment), as a substantive test, and in the overall review stage. A simple analytical procedure is comparing the current year’s gross profit margin to the prior year’s and investigating significant, unexpected fluctuations. This can provide evidence for multiple assertions, such as valuation and completeness.

Evaluating and Documenting Audit Evidence

The final phase of the evidence process is evaluation. The auditor must aggregate the evidence from all procedures to determine if it is sufficient and appropriate to support the audit opinion. This involves professional skepticism and judgment. You must consider the persuasiveness of the evidence, whether it contradicts other evidence, and if any remaining uncorrected misstatements are material, either individually or in aggregate.

All evidence gathered and conclusions reached must be properly documented in the audit documentation (workpapers). The audit file serves as the primary record of the evidence that supports the auditor’s report and demonstrates that the audit was performed in accordance with standards. It must be sufficiently detailed to enable an experienced auditor, with no prior connection to the audit, to understand the work performed, the evidence obtained, and the conclusions reached.

Common Pitfalls

1. Over-Reliance on Inquiry and Management Representations: Treating verbal explanations from management as conclusive evidence is a critical error. Inquiry is a starting point, not an endpoint. Always seek independent corroboration through inspection, confirmation, or other more reliable procedures.
2. Misapplying Procedures to Assertions: Selecting a procedure that does not directly test the assertion in question wastes time and fails to gather appropriate evidence. For instance, vouching a recorded transaction to a shipping document tests occurrence (that the transaction happened), but it does not test completeness (that all transactions are recorded). To test completeness, you would start from the shipping log and trace to the recorded sales.
3. Insufficient Professional Skepticism: Approaching an audit with a presumptive trust that management is honest can lead to overlooking contradictory evidence or accepting inadequate explanations. Professional skepticism is a mindset that includes a questioning mind and a critical assessment of audit evidence.
4. Ignoring Contradictory or Inconsistent Evidence: Sometimes, evidence gathered from one procedure conflicts with evidence from another (e.g., a high accounts receivable confirmation failure rate despite good analytical procedure results). Failing to investigate and resolve these inconsistencies can result in an incorrect audit opinion.

Summary

• Audit evidence is all information used to support the audit opinion, gathered to test specific financial statement assertions made by management.
• The auditor must obtain sufficient appropriate audit evidence. Sufficiency is the quantity; appropriateness is the quality (relevance and reliability), influenced by source, nature, and internal controls.
• The seven core audit procedures are inspection, observation, inquiry, confirmation, recalculation, reperformance, and analytical procedures. Each has strengths, limitations, and is best suited for testing particular assertions.
• Inquiry alone is never sufficient due to low reliability; it must be corroborated. Confirmation provides high-reliability external evidence.
• Evidence evaluation requires professional skepticism and judgment. All procedures, evidence, and conclusions must be thoroughly documented in the audit documentation to demonstrate compliance with auditing standards.