5
　　SPECIFIC ASPECTS OF AUDITING IN A COMPUTER-BASED
　　ENVIRONMENT
　　JANUARY 2011
　　this facility may be utilised by the auditor when auditing salaries and wages in
　　the client’s financial statements. Similarly, a facility to report trade payable
　?。╟reditor） long outstanding balances could be used by an auditor when
　　verifying the reported value of creditors.
　　Test data
　　Audit test data
　　Audit test data is used to test the existence and effectiveness of controls built
　　into an application program used by an audit client. As such, dummy
　　transactions are processed through the client’s computerised system. The
　　results of processing are then compared to the auditor’s expected results to
　　determine whether controls are operating efficiently and systems’
　　objectiveness are being achieved. For example, two dummy bank payment
　　transactions （one inside and one outside authorised parameters） may be
　　processed with the expectation that only the transaction processed within the
　　parameters is ‘accepted’ by the system. Clearly, if dummy transactions
　　processed do not produce the expected results in output, the auditor will need
　　to consider the need for increased substantive procedures in the area being
　　reviewed.
　　Integrated test facilities
　　To avoid the risk of corrupting a client’s account system, by processing test
　　data with the client’s other ‘live’ data, auditors may instigate special ‘test data
　　only’ processing runs for audit test data. The major disadvantage of this is that
　　the auditor does not have total assurance that the test data is being processed
　　in a similar fashion to the client’s live data. To address this issue, the auditor
　　may therefore seek permission from the client to establish an integrated test
　　facility within the accounting system. This entails the establishment of a
　　dummy unit, for example, a dummy supplier account against which the
　　auditor’s test data is processed during normal processing runs.
　　Other techniques
　　This section contains useful background information to enhance your overall
　　understanding.
　　Other CAATs include:
　　Embedded audit facilities （EAFs）
　　This technique requires the auditor’s own program code to be embedded
　?。╥ncorporated） into the client’s application software, such that verification
　　procedures can be carried out as required on data being processed. For
　　example, tests of control may include the reperformance of specific input
　　validation checks （see input controls above） – selected transactions may be
　　‘tagged’ and followed through the system to ascertain whether stated controls
　　and processes have been applied to those transactions by the computer
　　system. The EAFs should ensure that the results of testing are recorded in a
　　special secure file for subsequent review by the auditor, who should be able to
　　conclude on the integrity of the processing controls generally, from the results
　　of testing. A further EAF, often overlooked by students, is that of an analytical
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　　SPECIFIC ASPECTS OF AUDITING IN A COMPUTER-BASED
　　ENVIRONMENT
　　JANUARY 2011
　　review program enabling concurrent performance of analytical review
　　procedures on client data as it is being processed through the automated
　　system.
　　Application program examination
　　When determining the extent to which they may rely on application controls,
　　auditors need to consider the extent to which specified controls have been
　　implemented correctly. For example, where system amendments have
　　occurred during an accounting period, the auditor would need assurance as to
　　the existence of necessary controls both before and after the amendment. The
　　auditor may seek to obtain such assurance by using a software program to
　　compare the controls in place prior to, and subsequent to, the amendment
　　date.
　　Summary
　　The key objectives of an audit do not change irrespective of whether the audit
　　engagement is carried out in a manual or a computer-based environment. The
　　audit approach, planning considerations and techniques used to obtain
　　sufficient appropriate audit evidence do of course change. Students are
　　encouraged to read further to augment their knowledge of auditing in a
　　computer-based environment and to practise their ability to answer exam
　　questions on the topic by attempting questions set in previous ACCA exam
　　papers.
　　Brian Pine is examiner for CAT Paper 8