Pp 17-new

Hall, Accounting Information Systems, 8e
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Accounting Information Systems, 8e
James A. Hall
Chapter 17
IT Controls Part III:
Systems Development,
Program Changes, and
Application Controls

Objectives for Chapter 17
 Be familiar with the controls and audit tests
relevant to the systems development process.
 Understand the risks and controls associated
with program change procedures and the role
of the source program library.
 Understand the auditing techniques (CAATTs)
used to verify the effective functioning of
application controls.
 Understand the auditing techniques used to
perform substantive tests in an IT
environment.
2

Systems Development Controls
Controllable activities that distinguish an effective
systems development process include:
 Systems authorization
 User specification
 Technical design
 Internal audit participation
 Program testing
 User test and acceptance procedures
3

Auditor’s objectives
The auditor’s objectives are to ensure that
 all systems development activities are
applied consistently and follow
management’s policies
 system as originally implemented was free
from material errors and fraud
 system was judged necessary and justified
at checkpoints throughout the SDLC, and
 system documentation is sufficiently
accurate and complete to facilitate audit
and maintenance activities.
4

Tests of Systems Development
Controls
 New systems must be authorized.
 Feasibility studies were conducted.
 User needs were analyzed and addressed.
 Cost-benefit analysis was done.
 Proper documentation was completed.
 All program modules must be thoroughly
tested before they are implemented.
 Checklist of problems was kept.
5

System Maintenance Controls
 Last, longest and most costly phase of
systems development
 Up to 80-90% of entire cost of a
system
 All maintenance actions should require
 Technical specifications
 Testing
 Documentation updates
 Formal authorizations for any changes
6

Program Change
Audit objectives: detect unauthorized
program maintenance and determine
that...
 maintenance procedures protect
applications from unauthorized changes
 applications are free from material errors
 program libraries are protected from
unauthorized access
7

Source Program Library
 Source program library (SPL)
 library of applications and software
 place where programs are
developed and modified
 once compiled into machine
language, no longer vulnerable
8

Uncontrolled Access to the SPL
9
Figure 17-2

Controlled SPL Environments
 SPL Management Systems (SPLMS)
protect the SPL by controlling the
following functions:
 storing programs on the SPL
 retrieving programs for maintenance
purposes
 deleting obsolete programs from the
library
 documenting program changes to
provide an audit trail of the changes
10

Source Program Library under the
Control of SPL Management Software
11
Figure 17-3

SPL Control Features
 Password control
 Separation of test libraries
 Audit trails
 Reports that enhance management
control and the audit function
 Assigns program version numbers
automatically
 Controlled access to maintenance
commands 12

Program Change
 Auditing procedures: verify that
programs were properly maintained,
including changes
 Specifically, verify…
 identification and correction of
unauthorized program changes
 identification and correction of application
errors
 control of access to systems libraries
13

Testing Application Controls
 Techniques for auditing applications
fall into two classes:
1. testing application controls – two
general approaches:
– black box – around the computer
– white box – through the computer
2. examining transaction details and
account balances—substantive
testing
14

Auditing Around the Computer -
The Black Box Approach
15
Figure 17-9

Auditing through the Computer:
The ITF Technique
16Figure 17-14

 Black Box Approach – focuses on
input procedures and output results
 To Gain need understanding…
 analyze flowcharts
 review documentation
 conduct interviews
17

 Auditing through-the-computer
 focuses on understanding the internal logic
of processes between input and output
 Common tests
• Authenticity tests
• Accuracy tests
• Completeness tests
• Redundancy tests
• Access tests
• Audit trail tests
• Rounding error tests
18

Audit Testing Techniques
 Test data method: testing for logic or control
problems - good for new systems or systems
which have undergone recent maintenance
 base case system evaluation (BCSE) - using a
comprehensive set of test transactions
 tracing - performs an electronic walkthrough of
the application’s internal logic
 Test data methods are not fool-proof
 a snapshot - one point in time examination
 high-cost of developing adequate test data
19

Audit Testing Techniques
 Integrated test facility (ITF): an
automated, on-going technique that
enables the auditor to test an
application’s logic and controls during
its normal operation
 Parallel simulation: auditor writes
simulation programs and runs actual
transactions of the client through the
system
20

The Parallel Simulation Technique
21
Figure 17-11

Substantive Testing
 Techniques to substantiate account balances.
For example:
 search for unrecorded liabilities
 confirm accounts receivable to ensure they are
not overstated
 Requires first extracting data from the system.
Two technologies commonly used to select,
access, and organize data are:
 embedded audit module
 generalized audit software
22

Embedded Audit Module
 An ongoing module which filters out non-
material transactions
 The chosen, material transactions are
used for sampling in substantive tests
 Requires additional computing resources
by the client
 Hard to maintain in systems with high
maintenance
23

Embedded Audit Module Technique
24Figure 17-12

Generalized Audit Software
 Very popular & widely used
 Can access data files & perform
operations on them:
 screen data
 statistical sampling methods
 foot & balance
 format reports
 compare files and fields
 recalculate data fields
25

Using GAS to Access
Complex File Structure
26
Figure 17-14

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