Chapter%20Eight:%20Auditing%20Computerized%20Information%20Systems

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Chapter 8
Auditing Computerized Information Systems
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Computer Audit Tools to Test Computer Processing

• Elements of a systems audit approach.
• Only authorized computer applications are
  developed.
• Programs are thoroughly tested.
• Authorization needed for changes to programs.
• Access restricted.
• Controls over users and input.
• Monitoring controls in place.

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Computer Audit Tools to Test Computer Processing
(cont.)

• Data transmission controls in place.
• Data integrity is periodically tested.
• A comprehensive security and backup plan is in
  place.

4
Comprehensive Approach

• Auditors must always
• Independently test the correctness of processing
• Independently test the reliability of data

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Approaches to Address Correctness of Processing
Test data and integrated test facility
Concurrent processing
Embedded audit modules
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Test Data Auditing through the computer

• Test data approach
• Are control procedures functioning?
• Is the computer application processing
  transactions correctly?
• Are all transaction and master files fully and
  correctly updated?
• Limitations!
• Integrated test facility (ITF)

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Concurrent Processing Methodologies

• Tagging and tracing approach (a.k.a. snapshot
  approach)
• The systems control audit review file (SCARF)
  approach
• Embedded audit modules
• Advantages

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Using the Computer to Help Test Accounting Records

• Generalized Audit Software (GAS)
• Footing
• Selecting a sample
• Extracting, sorting, summarizing data
• Statistics
• Analytical review
• Screening
• Checking
• Calculations
• Reports

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Using the Computer to Help Test Accounting Records

• Custom Designed Audit Software
• Alternative to GAS
• Custom designed for specific client and specific
  application

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Unique Audit Approaches for Electronic Commerce

• Risk Analysis
• The Process and Control Audit
• Detailed testing of account balances
• Tagging and Tracing
• Embedded Audit Module
• Audit Software

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Use of Personal Computing in Conducting an Audit

• Traditional Uses
• Word Processing
• Spreadsheets
• Expanded uses
• Electronic working papers
• Groupware
• Intelligent agents
• Expert systems

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Unique Problems Auditing a Clients Spreadsheet

• Parallel simulation
• Test data
• Manual audit