An experienced auditor remarked that it is only necessary to check the additions and extensions on one invoice generated by an IT-based system, because if the computer program does one invoice correctly it will do them all correctly, so there is no point in testing a statistical sample of invoices.

Required:
a. Comment on whether or not you agree with this statement. Give your reasons.
b. Assume that a company had effective controls over program changes in prior years, but during the current year a new programmer was hired who was not qualified for the job and did not document changes to the programs that were made during the year.
Would this fact have an impact on your response for (a)?