Information technology audit process:
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In 1947, the American Institute of Certified Public Accountants (AICPA) adopted GAAS to establish standards for audits. The standards cover the following three categories:
The auditor must plan and conduct the audit to ensure their audit risk (the risk of reaching an incorrect conclusion based on the audit findings) will be limited to an acceptable level. To eliminate the possibility of assessing audit risk too low the auditor should perform the following steps:
The audit process can be broken down into the following audit phases:
This will allow the auditor to set the scope and objectives of the relationship between the auditor and the organization. The engagement letter should address the responsibility (scope, independence, deliverables), authority (right of access to information), and accountability (auditees’ rights, agreed completion date) of the auditor.
This phase of the audit allows the auditor to gather organizational information as a basis for creating their audit plan. The preliminary review will identify an organization’s strategy and responsibilities for managing and controlling computer applications. An auditor can provide an in depth overview of an organization’s accounting system to establish which applications are financially significant at this phase. Obtaining general data about the company, identifying financial application areas, and preparing an audit plan can achieve this.
In order to plan the audit, a preliminary judgment about materiality and assessment of the client’s business risks are made to set the scope of the audit.
Proper planning of the audit will ensure the audit is conducted in an effective and efficient manner. When developing the audit plan, the auditor sinto consideration the results of their understanding of the organization and the results of the risk assessment process.
To develop their understanding of internal controls, the auditor should consider information from previous audits, the assessment of inherent risk, judgments about materiality, and the complexity of the organization’s operations and systems.
Once the auditor develops their understanding of an organization’s internal controls, they will be able to assess the level of their control risk (the risk a material weakness will not be prevented or detected by internal controls).
Audit procedures are developed based on the auditor’s understanding of the organization and its environment. A substantive audit approach is used when auditing an organization’s information system.
Once audit procedures have been performed and results have been evaluated, the auditor will issue either an unqualified or qualified audit report based on their findings.
IS Standard 050 (Planning) states, “The IT auditor should plan the information systems audit coverage to address the audit objectives and comply with applicable laws and professional auditing standards.”
One of the first tasks an auditor must do when planning the audit is to develop a working budget. The IT audit manager must know the capabilities of the audit staff assigned to the project. In addition to budgeted time needed to perform the audit, the IT audit manager should also budget time needed to train the audit staff (if needed) and allow time for any error correction purposes.
While planning the audit, the auditor decides what level of audit risk (the risk of reaching an incorrect conclusion based on the audit findings) he or she is willing to accept. The more effective and extensive the audit work is, the less the risk that a weakness will go undetected and the auditor will issue an inappropriate report. Audit risk is dependent on the auditors assessed levels of inherent risk (the susceptibility of an audit area to error which could be material, assuming there are no related internal controls), control risk (the risk a material weakness will not be prevented or detected by internal controls), and detection risk (the risk substantive tests will not detect an error which could be material). These risks are determined when the auditor performs a risk assessment of the organization.
Additionally, in order to evaluate whether an IT audit has been successful, the auditor must first identify the intended scope and objectives of the audit to test management’s assertions on their information systems. To meet the audit objectives, and to ensure that audit resources will be used efficiently, the auditor will need to establish levels of materiality. The auditor should consider both qualitative and quantitative aspects in determining materiality. An assessment of risk should be made to provide reasonable assurance that all material items will be adequately covered during the audit work. This assessment should identify areas with relatively high risk of existence of material problems.
In assessing materiality, the IT auditor should consider:
While establishing materiality, the auditor may audit non-financial items such as physical access controls, logical access controls, and systems for personnel management, manufacturing control, design, quality control, and password generation.
While planning the audit work to meet the audit objectives, the auditor should identify relevant control objectives and determine, based on materiality, which controls should be examined. Internal control objectives are placed by management and identifies what the management strives to achieve through their internal controls.
Where financial transactions are not processed, the following identifies some measures the auditor should consider when assessing materiality:
A risk is any event or action, generated internally or externally, which prevents an organization from achieving its goals and/or objectives. Risks affect control objectives in the areas of data integrity and accuracy, timeliness of the information for decision making, ability to access the system, and confidentiality/privacy of information, to name a few. Risk assessment allows the auditor to determine the scope of the audit and assess the level of audit risk and error risk (the risk of errors occurring in the area being audited). Additionally, risk assessment will aid in planning decisions such as:
Once the assessed level of risk has been determined, the auditor should document the following in their work papers:
The audit plan details the audit objectives and steps the auditor must take to ensure all of the important issues in the audit are covered. The audit plan includes:
The objective of the audit plan is to assist the auditor in conducting an effective and efficient audit.
A planning memo outlines for the auditee the tone and course of action the IT audit manager plans to take. The memo outlines for the auditee the areas within the audit the auditor is planning to spend most of their time, and it gives the auditee the opportunity to voice any concerns.
COSO defines internal control as, “a process, influenced by an entity’s board of directors, management, and other personnel, that is designed to provide reasonable assurance in the effectiveness and efficiency of operations, reliability of financial reporting, and the compliance of applicable laws and regulations”. The auditor evaluates the organization’s control structure by understanding the organization’s five interrelated control components. They include:
In addition to understanding the organization’s control components, the auditor must also evaluate the organization’s General and Application controls. there are three audit risk componenets which are control risk, detection risk and inherent risk.
General controls relate to the overall information-processing environment and has a large effect on the organization’s computer operations. Types of general controls include:
Application controls apply to the processing of individual accounting applications and help ensure the completeness and accuracy of transaction processing, authorization, and validity. Types of application controls include:
Application controls may be compromised by the following application risks:
Tests of controls are audit procedures performed to evaluate the effectiveness of either the design or the operation of an internal control. Tests of controls directed toward the design of the control focuses on evaluating whether the control is suitably designed to prevent material weaknesses. Tests of controls directed toward the operation of the control focuses on assessing how the control was applied, the consistency with which it was applied, and who applied it. In addition to inquiring with appropriate personnel and observation of the application of the control, an IT auditor’s main focus when testing the controls is to do a re-performance of the application of the control themselves.
Audit sampling is the application of an audit procedure to less than 100% of the population to enable the IT auditor to evaluate audit evidence within a class of transactions for the purpose of forming a conclusion concerning the population. When designing the size and structure of an audit sample, the IT auditor should consider the audit objectives determined when planning the audit, the nature of the population, and the sampling and selection methods.
The auditor should select the sample items in such a way that they are representative of the population. The most commonly used sampling selection methods are:
The selection of the sample size is affected by the level of sampling risk that the IT auditor is willing to accept. Sampling risk is the risk the auditor’s conclusion may be different from the conclusion that would be reached if the entire population were subjected to the same audit procedure. The two types of sampling risk are:
Once the sample items have been selected to be tested, the auditor can begin audit tests using Computer Assisted Auditing Techniques (CAATs), which will be discussed shortly.
The performance and evaluation of a sample must address the following issues:
The auditor must document in their work papers the sampling objectives and the sampling process used. The work papers should include the source of the population, the sampling method used, sampling parameters, items selected, details of audit tests performed, and conclusions reached.
CAATs are used to test application controls as well as perform substantive tests on sample items. Types of CAATs include:
Through the use of CAATs, the auditor will be able to obtain evidence to support their final conclusions developed on the audit. Audit evidence should be sufficient, reliable, relevant, and useful in order for the auditor to form an opinion and to support their findings and conclusions. If the auditor cannot form an opinion based on the audit evidence obtained, the auditor should then obtain additional audit evidence. Procedures used to gather audit evidence varies depending on the information system being audited. The auditor should select the most appropriate procedure for the audit objective. The following procedures should be considered:
The audit evidence gathered by the auditor should be documented and organized to support the auditor’s findings and conclusions. Finally, when an auditor believes that sufficient audit evidence cannot be obtained, the auditor should disclose this fact as a scope limitation within the audit report.
Before choosing the appropriate audit report, the auditor must consider the following issues:
Audit procedures used to review for subsequent events include asking management whether any unusual adjustments to their information systems have been made during the subsequent events period (after the completion of the audit, but before the audit report is issued), or obtaining a representation letter from management.
The auditor’s conclusion and findings, which are based on documented evidence, must be objective, measurable, complete, and relevant. The findings are disclosed to management in formal statements, typically an audit report. Any recommendations must be provided for each audit finding for the report to be useful to management.
IS Auditing Standard 070 (Reporting) states, “The IT auditor should provide a report in an appropriate form, upon the completion of the audit. The report should state the scope, objectives, period of coverage, and the nature, timing, and extent of the audit work performed. The report should state the findings, conclusions, and recommendations and any reservations, qualifications or limitations of scope that IT auditor has with respect to the audit.”
Working papers (audit documentation) is the formal collection of auditors notes, documents, flowcharts, correspondence, results of observations, plans and results of tests, the audit plan, minutes of meetings, computerized records, data files or application results