Computer Assisted audit techniques (CAAT) may be required in a CIS environment in the following circumstances:
The absence of input documents (e.g. order entry in on-line systems) or the generation of accounting transactions computer programs (e.g. automatic calculation of discounts) may preclude the auditor from examining documentary evidence.
The lack of a visible audit trail will preclude the auditor from visually following transactions through the computerized accounting system.
The lack of visible output may necessitate access to data retained on files readable only the computer.
The effectiveness and efficiency of auditing procedures may be improved through the use of computer- assisted audit techniques in obtaining and evaluating audit evidence, for example:
Some transactions may be tested more effectively for a similar level of cost using the computer to examine all or a greater number of transactions than would otherwise be selected.
In applying analytical review procedures, transactions or balance details may be reviewed and reports printed of unusual items more efficiently using the computer than manual methods.