Audit Evidence: Types, Examples & Reliability for Asset Audits

Audit evidence is the information an auditor gathers to support the conclusions in an audit opinion — and it must be both sufficient and appropriate (relevant and reliable) to be credible. This guide breaks down the 8 types of audit evidence — from physical examination to reperformance — with concrete examples and a reliability hierarchy, and shows how CPCON Group leverages every evidence type to deliver accurate, compliant inventory and fixed asset audits.

What is Audit Evidence?

Audit evidence is the information an auditor gathers to support the conclusions in an audit opinion; it must be sufficient (enough) and appropriate (relevant and reliable). This definition aligns with auditing standards such as AU-C 500 and ISA 500.

In inventory and fixed asset audits, audit evidence must be sufficient, appropriate, and reliable to ensure accuracy and compliance with accounting standards such as GAAP, IFRS, and regulatory requirements.

The quality and quantity of audit evidence directly impact the credibility of audit results. Through its fixed asset audit and verification services and physical inventory counting services, CPCON Group specializes in gathering comprehensive audit evidence across multiple categories to deliver defensible, audit-ready reports for financial reporting, compliance, and operational decision-making.

8 Types of Audit Evidence

1

Physical Examination

Physical examination involves direct inspection and verification of tangible assets. This is the most reliable form of audit evidence for inventory and fixed asset audits.

Examples in Practice:

  • Physically counting inventory items in warehouses and distribution centers
  • Inspecting fixed assets (machinery, equipment, vehicles) to verify existence and condition
  • Verifying serial numbers, asset tags, and identification labels
  • Assessing physical condition for impairment testing

CPCON Approach: Our field teams conduct comprehensive physical examinations using barcode scanners, RFID technology, and mobile data collection devices to ensure 99%+ accuracy in asset verification.

2

Documentation

Documentary evidence includes written or electronic records that support asset existence, ownership, valuation, and transactions.

Key Documents:

  • Purchase orders, invoices, and receipts
  • Fixed asset registers and depreciation schedules
  • Inventory management system reports
  • Lease agreements and title documents
  • Maintenance records and warranty documentation
  • Insurance policies and appraisal reports

CPCON Approach: We systematically review and cross-reference documentation from multiple sources, including ERP systems (SAP, Oracle, JD Edwards), to validate asset records and identify discrepancies.

3

Observation

Observation involves watching processes, procedures, and activities performed by client personnel to assess controls and operational effectiveness.

What We Observe:

  • Inventory receiving and put-away procedures
  • Cycle counting and physical inventory processes
  • Asset tagging and labeling practices
  • Security controls and access restrictions
  • Warehouse layout and storage conditions

CPCON Approach: Our auditors observe client operations to identify control weaknesses, process inefficiencies, and opportunities for improvement in inventory and asset management.

4

Confirmation

Confirmation is the process of obtaining direct written responses from independent third parties to verify information.

Common Confirmations:

  • Third-party warehouse inventory confirmations
  • Consignment inventory held by customers or vendors
  • Equipment on lease or rental agreements
  • Assets held as collateral by lenders

CPCON Approach: We coordinate with third parties to obtain independent confirmations, ensuring assets recorded in client systems actually exist at external locations.

5

Analytical Procedures

Analytical procedures involve evaluating financial and operational data by studying relationships, trends, and ratios to identify anomalies.

Analytical Techniques:

  • Inventory turnover ratio analysis
  • Variance analysis (expected vs. actual inventory levels)
  • Trend analysis of asset acquisitions and disposals
  • Depreciation expense reasonableness testing
  • Obsolescence and shrinkage pattern identification

CPCON Approach: Our data analytics team uses advanced tools to perform statistical analysis, identify outliers, and flag high-risk areas requiring detailed investigation.

6

Inquiry

Inquiry involves seeking information from knowledgeable persons inside or outside the organization through formal or informal questioning.

Who We Interview:

  • Warehouse managers and inventory control staff
  • Accounting and finance personnel
  • Procurement and purchasing teams
  • IT system administrators
  • External appraisers and valuation experts

CPCON Approach: We conduct structured interviews to understand processes, controls, and potential issues. Inquiry evidence is always corroborated with other evidence types for reliability.

7

Recalculation

Recalculation involves independently checking the mathematical accuracy of documents, records, and calculations.

What We Recalculate:

  • Depreciation calculations and useful life assumptions
  • Inventory valuation (FIFO, LIFO, weighted average)
  • Lower of cost or market adjustments
  • Capitalization thresholds and componentization
  • Impairment testing calculations

CPCON Approach: We independently recalculate key figures — depreciation schedules, inventory valuation, and impairment math — to verify accuracy and identify calculation errors or system issues.

8

Reperformance

Reperformance means independently re-executing a control or procedure that was originally performed by the client, to confirm it produces the same result.

What We Reperform:

  • Re-running a cycle count and comparing it to the client's result
  • Re-executing an inventory or fixed-asset reconciliation
  • Re-performing a tagging-to-register match for sampled assets
  • Re-applying a control such as a count-sheet approval or cutoff test

CPCON Approach: We reperform critical controls and procedures to verify they operate as intended and to surface gaps between recorded and actual results.

Audit Evidence Examples

Each type of audit evidence shows up differently in a real inventory or fixed asset audit. Here are concrete audit evidence examples, one per type:

  • Physical examination — counting inventory items and inspecting machinery on the warehouse floor
  • Confirmation — a signed bank letter or a third-party warehouse stating quantities held
  • Documentation — invoices, purchase orders, the fixed-asset register, and lease agreements
  • Observation — watching the physical-inventory process as it is performed
  • Inquiry — interviewing the warehouse manager about cycle-count procedures
  • Analytical procedures — inventory turnover ratio and variance analysis
  • Recalculation — re-checking a depreciation schedule for mathematical accuracy
  • Reperformance — independently re-running a cycle count and comparing the result

Audit Evidence Reliability Hierarchy

Not all audit evidence is equally reliable. Understanding the hierarchy helps prioritize evidence collection:

Most Reliable

  • Evidence obtained directly by the auditor (physical examination, observation)
  • External evidence from independent third parties (confirmations)

Moderately Reliable

  • Documentary evidence from external sources (invoices, contracts)
  • Internal documentation with strong controls

Less Reliable

  • Internal documentation with weak controls
  • Oral evidence (inquiry) without corroboration

Best Practices for Collecting Audit Evidence

Sufficiency

Collect enough evidence to support conclusions. Sample sizes should be statistically valid and representative of the population.

Appropriateness

Evidence must be relevant to the audit objective and reliable based on its source and nature.

Corroboration

Use multiple types of evidence to corroborate findings. Cross-reference physical counts with system records and documentation.

Documentation

Maintain comprehensive audit workpapers documenting all evidence collected, procedures performed, and conclusions reached.

The CPCON Advantage in Audit Evidence Collection

Across 30+ years and four continents, CPCON Group has conducted thousands of inventory and fixed asset audits, developing proprietary methodologies for collecting comprehensive, defensible audit evidence.

99%+
Asset Verification Accuracy
8
Evidence Types Used
100%
Audit-Ready Reports

Technology-Enabled Evidence Collection: We use barcode scanners, RFID readers, mobile apps, and cloud-based platforms to capture real-time evidence with photo documentation and GPS coordinates.

Multi-Source Verification: Every asset is verified using at least three types of evidence (physical examination, documentation, and system records) to ensure accuracy.

Compliance-Ready Documentation: Our audit workpapers meet GAAP, IFRS, SOX, and industry-specific regulatory requirements, ready for external auditor review.

Expert Analysis: Our CPAs, CVAs, and industry specialists analyze evidence to identify control weaknesses, valuation issues, and opportunities for improvement.

Audit Evidence FAQs

What is audit evidence?

Audit evidence is the information an auditor gathers to support the conclusions in an audit opinion. To support those conclusions it must be both sufficient (enough in quantity) and appropriate (relevant and reliable in quality), consistent with auditing standards such as AU-C 500 and ISA 500.

What are the 8 types of audit evidence?

The 8 types of audit evidence are: (1) Physical examination — direct inspection and verification of tangible assets, (2) Documentation — written or electronic records supporting asset existence and valuation, (3) Observation — watching processes and procedures performed by client personnel, (4) Confirmation — obtaining direct written responses from independent third parties, (5) Analytical procedures — evaluating financial data by studying relationships, trends, and ratios, (6) Inquiry — seeking information from knowledgeable persons through questioning, (7) Recalculation — checking the mathematical accuracy of records and calculations, and (8) Reperformance — independently re-executing a control or procedure.

What are some examples of audit evidence?

Examples of audit evidence include: physical examination — counting inventory items and inspecting machinery on the warehouse floor; confirmation — a signed bank letter or a third-party warehouse stating quantities held; documentation — invoices, purchase orders, the fixed-asset register, and lease agreements; observation — watching the physical-inventory process; inquiry — interviewing the warehouse manager; analytical procedures — inventory turnover ratio and variance analysis; recalculation — re-checking a depreciation schedule; and reperformance — independently re-running a cycle count.

Which type of audit evidence is most reliable?

Evidence obtained directly by the auditor, such as physical examination and observation, is the most reliable. External evidence from independent third parties (confirmations) is also highly reliable. Documentary evidence from external sources like invoices and contracts is moderately reliable, while internal documentation with weak controls and oral evidence from inquiry without corroboration are considered less reliable.

What is the difference between inspection and observation in auditing?

Physical inspection (examination) involves directly verifying tangible assets — counting inventory items, inspecting fixed assets, and verifying serial numbers and asset tags to confirm existence and condition. Observation involves watching processes, procedures, and activities performed by client personnel to assess controls and operational effectiveness, such as observing inventory receiving procedures, cycle counting processes, and security controls.

How do auditors evaluate the sufficiency of audit evidence?

Auditors evaluate sufficiency by ensuring enough evidence is collected to support conclusions, with sample sizes that are statistically valid and representative of the population. Evidence must also be appropriate — relevant to the audit objective and reliable based on its source and nature. Best practice is to use multiple types of evidence to corroborate findings, cross-referencing physical counts with system records and documentation.

What is analytical procedure as audit evidence?

Analytical procedures involve evaluating financial and operational data by studying relationships, trends, and ratios to identify anomalies. Key techniques include inventory turnover ratio analysis, variance analysis comparing expected versus actual inventory levels, trend analysis of asset acquisitions and disposals, depreciation expense reasonableness testing, and obsolescence and shrinkage pattern identification.

Need Expert Audit Evidence Collection?

Partner with CPCON Group for comprehensive inventory and fixed asset audits backed by multiple types of reliable audit evidence. Our proven methodologies ensure accuracy, compliance, and defensible results.