Audit Evidence and Auditing Procedure – Comprehensive Notes
Learning Outcomes
By the end of this topic you should be able to:
Explain the concept, forms and sources of audit evidence.
Distinguish and list the several types of evidences used in auditing.
Interpret the meaning of “sufficiency” (quantity) and “appropriateness” (quality) of evidence.
Describe the link between evidence gathered and the auditor’s final opinion.
Definition of Audit Evidence
“Audit Evidence” = all information obtained by the auditor to reach the conclusions on which the audit opinion is based.
Encompasses both:
Underlying accounting data.
Corroborating information from any source.
Key Decisions When Designing Audit Evidence
Which audit procedures to perform.
What sample size to choose for each procedure.
Which specific items within the population to test.
Timing – when in the audit cycle the procedures should be carried out.
Governing Standard – ISA 500 “Audit Evidence”
Requires the auditor to obtain sufficient appropriate audit evidence (SAAE) to draw reasonable conclusions.
Terms in ISA 500:
Sufficient = enough evidence (quantity).
Appropriate = relevant + reliable (quality).
Reasonable basis = rational support for the opinion; not absolute certainty.
Components of Audit Evidence
1. Underlying Accounting Data
Books of original entry (sales journals, purchase journals, cashbooks, etc.).
General & subsidiary ledgers.
Accounting manuals and chart of accounts.
Informal / memorandum records: working papers, schedules, reconciliations, spreadsheets.
2. Corroborating Information
External & internal documents: cheques, EFT authorisations, invoices, shipping docs, contracts.
Written confirmations & management representations.
Evidence generated from:
Inquiry, observation, inspection, physical examination.
Any other information the auditor develops (e.g. analytical ratios).
3. Statutory Backdrop (Malaysia – Companies Act 1965 §167)
Companies must keep records “sufficient to explain transactions and financial position”.
Entries must be recorded within 60 days of the transaction.
Retention period ≥ 7 years.
Overseas records allowed, but copies must be maintained in Malaysia.
Nature of Audit Evidence
Persuasive rather than conclusive – the auditor rarely examines 100 % of information.
To strengthen persuasiveness, auditors seek evidence:
From different sources (external vs internal, third-party vs client-generated).
Of different nature (physical, documentary, oral, analytical) supporting the same assertion.
Persuasiveness Determinants
Sufficiency – quantity of evidence.
Appropriateness – quality (relevance + reliability).
Sufficiency – Quantity Considerations
Influenced by:
Materiality: high materiality ⇒ more evidence.
Inherent & control risk: higher risk ⇒ larger sample.
Economic factors: cost-benefit trade-off.
Population size & characteristics: heterogeneous populations may require more items.
Sampling can be judgemental or statistical.
Appropriateness – Reliability Factors
Source independence: third-party > client.
Effective internal controls: strong controls → system-generated evidence more reliable.
Auditor’s direct knowledge: evidence obtained firsthand (e.g. physical count) is highest.
Documentary vs oral: written/electronic > verbal (oral can be retracted).
Originals vs copies: originals > photocopies/faxes (risk of alteration).
Professional Skepticism & Evaluation (AI 200)
Auditor must maintain a questioning mind and critically assess all evidence.
Evidence evaluation skills are essential: thorough, unbiased, and alert to contradictory information.
How Evidence Is Obtained – The Two Broad Categories
Tests of Controls (TOC) – evaluate operating effectiveness of internal controls at the assertion level.
Substantive Procedures (SP) – obtain direct evidence regarding amounts & disclosures.
In some audits evidence may come entirely from substantive procedures (ISA 500 §3).
Tests of Controls (TOC)
Objective: confirm that internal controls prevent / detect / correct misstatements.
Typical procedures:
Inquiry of client personnel.
Inspection of docs/records & walkthroughs.
Observation of control activities.
Re-performance of control steps by auditor.
Extent decisions:
Can rely on prior-year evidence (if controls unchanged & still effective).
Controls over significant risks demand more current testing.
Controls may be tested for less than the full year (e.g. rotational testing).
Substantive Procedures (SP)
Provide direct evidence on fair presentation of F/S assertions.
Three sub-types:
Analytical Procedures (AP)
Tests of Details of Transactions (TDT)
Tests of Details of Balances (TDB)
1. Analytical Procedures (ISA 520)
Evaluate financial information by analysing plausible relationships among data.
Comparisons with:
Prior periods.
Budgets / forecasts / auditor expectations.
Industry averages.
Relationship analysis:
Within financial data (e.g. gross margin =\frac{Gross\ Profit}{Sales}).
Between financial and non-financial data (e.g. payroll cost per employee).
Purposes:
Understand industry & business.
Assess going-concern.
Highlight possible misstatements.
Reduce other detailed tests.
Timing:
Required in planning.
Often used in fieldwork.
Required in completion (overall review).
2. Tests of Details of Transactions (TDT)
Examine support for individual debits/credits.
Example: vouch sales in Sales Day Book (SDB) to invoices & shipping docs.
3. Tests of Details of Balances (TDB)
Directly substantiate closing balances.
Example: confirm accounts receivable with customers.
Standard Audit Evidence Procedures
Physical Examination
External Confirmations
Documentation
Analytical Procedures
Inquiry of client
Re-performance
Observation
Detailed Discussion of Individual Evidence Types
Physical Examination
Auditor’s inspection or count of tangible assets (inventory, cash, PPE).
High reliability (direct, tangible, firsthand).
Confirmation
Obtain a representation of information or condition directly from a 3rd party.
Common confirmations & sources:
Cash – Bank.
Account / Notes Receivable – Customers / Makers.
Inventory on consignment – Consignee / Public warehouse.
Account / Notes Payable – Creditors / Lenders.
Shares outstanding – Registrar / Transfer Agent.
Insurance cover – Insurance company.
Reliability depends on:
Form (positive, negative, blank).
Prior experience with entity (response rates, accuracy).
Nature of information (simple balances > complex info).
Competence & independence of respondent.
Inspection of Records & Documents
Examination of internal or external documents (paper, electronic, or other media).
Provides evidence for existence, completeness, rights & obligations, etc.
Analytical Procedures (re-emphasised)
Study & comparison of relationships to flag unusual trends.
Evaluate financial information by analysing plausible relationships among data.
These procedures also involve investigating unusual fluctuations or inconsistencies that do not align with other relevant information or expected patterns.
Comparisons with:
Prior periods.
Anticipated results, such as budgets, forecasts, or auditor’s own estimates (e.g., estimated depreciation)
Similar industry information, like comparing sales-to-receivables ratios with industry averages or similar-sized entities in the same sector
Relationship analysis:
Within financial data that should follow predictable patterns (e.g., gross margin percentages based on past trends)
Between financial and non-financial data (e.g. payroll cost per employee).
Analytical procedure
Understand the client’s industry and business.
Assess the entity’s ability to continue as a
going concern
Highlight possible misstatements.
Reduce other detailed tests.
Emphasizes the expectations developed by the auditor
Required in planning phase.
Often done during the testing phase
Required in completion phase.
Inquiries of the client
Written or oral info obtained from client.
Low reliability alone; usually corroborated.
Re-calculation
Auditor independently rechecking a sample of calculations made by client(e.g. depreciation, interest, payroll).
Re-performance
Auditor re-perform or examines the client’s internal accounting procedures or controls.
Observation
Auditor uses their senses (seeing, hearing, etc.) to watch how the client performs certain activities (e.g. stock count attendance, plant tour).
Documentation
Auditor examines written records or documents to gather audit evidence
Example extract (inventory):
Compare quantity on perpetual records to quantities counted by client.
Hierarchy of Evidence Reliability (from most → least)
Physical examination & auditor computation (direct, objective).
Inspection of documentation, external confirmations, analytical procedures.
Inquiry of client personnel / management, observation (subjective, easily manipulated).