287.E计算机审计在中小型企业中的应用 外文原文.doc

INTERNATIONAL AUDITING PRACTICE STATEMENT 1009COMPUTER-ASSISTED AUDIT TECHNIQUESCONTENTS(This Statement is effective)ParagraphsIntroduction . . 1-3Description of Computer-Assisted Audit Techniques (CAATs) . . 4-6Considerations in the Use of CAATs . . 7-16Using CAATs . . 17-25Using CAATs in Small Entity IT Environments . . 26InternationalAuditingPracticeStatement(IAPS)1009,“Computer-AssistedAudit Techniques” should be read in the context of the “Preface to the International Standards on Quality Control, Auditing, Assurance and Related Service,” which sets out the application and authority of IAPSs.The IAPC approved this International Auditing Practice Statement in June 2001 for publication in July 2001.IAPS 1009COMPUTER-ASSISTED AUDIT TECHNIQUESIntroduction1.The overall objectives and scope of an audit do not change when an audit is conducted in a computer information technology (IT) environment. The application of auditing procedures may, however, require the auditor to consider techniques known as Computer- Assisted Audit Techniques (CAATs) that use the computer as an audit tool.2.CAATs may improve the effectiveness and efficiency of auditing procedures. They may also provide effective tests of control and substantive procedures where there are no input documents or a visible audit trail, or where population and sample sizes are very large.3.The purpose of this Statement is to provide guidance on the use of CAATs. It applies to all uses of CAATs involving a computer of any type or size. Special considerations relating to small entity IT environments are discussed in paragraph 26.Description of Computer Assisted Audit Techniques (CAATs)4.This Statement describes computer assisted audit techniques including computer tools, collectively referred to as CAATs. CAATs may be used in performing various auditing procedures, including the following:Tests of details of transactions and balances, for example, the use of audit software for recalculating interest or the extraction of invoices over a certain value from computer records.Analytical procedures, for example, identifying inconsistencies or significant fluctuations.Tests of general controls, for example, testing the set-up or configuration of the operating system or access procedures to the program libraries or by using code comparison software to check that the version of the program in use is the version approved by management.Sampling programs to extract data for audit testing.Tests of application controls, for example, testing the functioning of a programmed control.Reperforming calculations performed by the entitys accounting systems.5.CAATs are computer programs and data the auditor uses as part of the audit procedures to process data of audit significance contained in an entitys information systems. The data may be transaction data, on which the auditor wishes to perform tests of controls or substantive procedures, or they may be other types of data. For example, details of the application of some general controls may be kept in the form of text or other files by applications that are not part of the accounting system. The auditor can use CAATS to review those files to gain evidence of the existence and operation of those controls. CAATS may consist of package programs, purpose-written programs, utility programs or system management programs. Regardless of the origin of the programs, the auditor substantiates their appropriateness and validity for audit purposes before using them.Package programs are generalized computer programs designed to perform data processing functions, such as reading data, selecting and analyzing information,2IAPS 1009COMPUTER-ASSISTED AUDIT TECHNIQUESperforming calculations, creating data files and reporting in a format specified by the auditor.Purpose-written programs perform audit tasks in specific circumstances. These programs may be developed by the auditor, the entity being audited or an outside programmer hired by the auditor. In some cases the auditor may use an entitys existing programs in their original or modified state because it may be more efficient than developing independent programs.Utility programs are used by an entity to perform common data processing functions, such as sorting, creating and printing files. These programs are generally not designed for audit purposes, and therefore may not contain features such as automatic record counts or control totals.System management programs are enhanced productivity tools that are typically part of a sophisticated operating systems environment, for example, data retrieval software or code comparison software. As with utility programs, these tools are not specifically designed for auditing use and their use requires additional care.Embedded audit routines are sometimes built into an entitys computer system to provide data for later use by the auditor. These include the following:Snapshots: This technique involves taking a picture of a transaction as it flows through the computer systems. Audit software routines are embedded at different points in the processing logic to capture images of the transaction as it progresses through the various stages of the processing. Such a technique permits an auditor to track data and evaluate the computer processes applied to the data.System Control Audit Review File: This involves embedding audit software modules within an application system to provide continuous monitoring of the systems transactions. The information is collected into a special computer file that the auditor can examine.Test data techniques are sometimes used during an audit by entering data (for example, a sample of transactions) into an entitys computer system, and comparing the results obtained with predetermined results. An auditor might use test data to:Test specific controls in computer programs, such as on-line password and data access controls;Test transactions selected from previously processed transactions or created by the auditor to test specific processing characteristics of an entitys information systems. Such transactions are generally processed separately from the entitys normal processing; andTest transactions used in an integrated test facility where a “dummy” unit (for example, a fictitious department or employee) is established, and to which test transactions are posted during the normal processing cycle.When test data are processed with the entitys normal processing, the auditor ensures that the test transactions are subsequently eliminated from the entitys accounting records.IAPS 10093COMPUTER-ASSISTED AUDIT TECHNIQUES6.The increasing power and sophistication of PCs, particularly laptops, has resulted in other tools for the auditor to use. In some cases, the laptops will be linked to the auditors main computer systems. Examples of such techniques include:Expert systems, for example in the design of audit programs and in audit planning and risk assessment;Tools to evaluate a clients risk management procedures;Electronic working papers, which provide for the direct extraction of data from the clients computer records, for example, by downloading the general ledger for audit testing; andCorporate and financial modeling programs for use as predictive audit tests. These techniques are more commonly referred to as “audit automation.”Considerations in the Use of CAATs7.When planning an audit, the auditor may consider an appropriate combination of manual and computer assisted audit techniques. In determining whether to use CAATs, the factors to consider include:The IT knowledge, expertise and experience of the audit team;The availability of CAATs and suitable computer facilities and data;The impracticability of manual tests;Effectiveness and efficiency; andTiming.Before using CAATS the auditor considers the controls incorporated in the design of the entitys computer systems to which the CAATS would be applied in order to determine whether, and if so, how, CAATs should be employed.IT Knowledge, Expertise, and Experience of the Audit Team8.ISA 401 “Auditing in a Computer Information Systems Environment” deals with the level of skill and competence the audit team needs to conduct an audit in an IT environment. It provides guidance when an auditor delegates work to assistants with IT skills or when the auditor uses work performed by other auditors or experts with such skills. Specifically, the audit team should have sufficient knowledge to plan, execute and use the results of the particular CAAT adopted. The level of knowledge required depends on the complexity and nature of the CAAT and of the entitys information system.Availability of CAATs and Suitable Computer Facilities9.The auditor considers the availability of CAATs, suitable computer facilities (controlled as described in paragraphs 18-23) and the necessary computer-based information systems and data. The auditor may plan to use other computer facilities when the use of CAATs on an entitys computer is uneconomical or impractical, for example, because of an incompatibility between the auditors package program and the entitys computer. Additionally, the auditor may elect to use their own facilities, such as PCs or laptops.4IAPS 1009COMPUTER-ASSISTED AUDIT TECHNIQUES10.The cooperation of the entitys personnel may be required to provide processing facilities at a convenient time, to assist with activities such as loading and running of the CAATs on the entitys system, and to provide copies of data files in the format required by the auditor.Impracticability of Manual Tests11.Some audit procedures may not be possible to perform manually because they rely on complex processing (for example, advanced statistical analysis) or involve amounts of data that would overwhelm any manual procedure. In addition, many computer information systems perform tasks for which no hard copy evidence is available and, therefore, it may be impracticable for the auditor to perform tests manually. The lack of hard copy evidence may occur at different stages in the business cycle.Source information may be initiated electronically, such as by voice activation, electronic data imaging, or point of sale electronic funds transfer. In addition, some transactions, such as discounts and interest calculations, may be generated directly by computer programs with no specific authorization of individual transactions.A system may not produce a visible audit trail providing assurance as to the completeness and accuracy of transactions processed. For example, a computer program might match delivery notes and suppliers invoices. In addition, programmed control procedures, such as checking customer credit limits, may provide hard copy evidence only on an exception basis.A system may not produce hard copy reports. In addition, a printed report may contain only summary totals while computer files retain the supporting details.Effectiveness and Efficiency12.The effectiveness and efficiency of auditing procedures may be improved by using CAATs to obtain and evaluate audit evidence. CAATs are often an efficient means of testing a large number of transactions or controls over large populations by:Analyzing and selecting samples from a large volume of transactions;Applying analytical procedures; andPerforming substantive procedures.13.Matters relating to efficiency that an auditor might consider include:The time taken to plan, design, execute and evaluate a CAAT;Technical review and assistance hours;Designing and printing of forms (for example, confirmations); andAvailability of computer resources.14.In evaluating the effectiveness and efficiency of a CAAT, the auditor considers the continuing use of the CAAT application. The initial planning, design and development of a CAAT will usually benefit audits in subsequent periods.IAPS 10095COMPUTER-ASSISTED AUDIT TECHNIQUESTiming15.Certain data, such as transaction details, are often kept for only a short time, and may not be available in machine-readable form by the time the auditor wants them. Thus, the auditor will need to make arrangements for the retention of data required, or may need to alter the timing of the work that requires such data.16.Where the time available to perform an audit is limited, the auditor may plan to use a CAAT because its use will meet the auditors time requirement better than other possible procedures.Using CAATs17.The major steps to be undertaken by the auditor in the application of a CAAT are to: (a)Set the objective of the CAAT application;(b)Determine the content and accessibility of the entitys files; (c)Identify the specific files or databases to be examined;(d)Understand the relationship between the data tables where a database is to be examined;(e)Define the specific tests or procedures and related transactions and balances affected;(f)Define the output requirements;(g)Arrange with the user and IT departments, if appropriate, for copies of the relevant files or database tables to be made at the appropriate cut off date and time;(h)Identify the personnel who may participate in the design and application of theCAAT;(i)Refine the estimates of costs and benefits;(j)Ensure that the use of the CAAT is properly controlled and documented;(k)Arrange the administrative activities, including the necessary skills and computer facilities;(l)Reconcile data to be used for the CAAT with the accounting records; (m)Execute the CAAT application; and(n)Evaluate the results.Controlling the CAAT Application18.The specific procedures necessary to control the use of a CAAT depend on the particular application. In establishing control, the auditor considers the need to:(a)Approve specifications and conduct a review of the work to be performed by t