Test-check audit
In one sentenceAn audit in which the auditor examines a selected sample of transactions and then forms an opinion on the whole population based on the sample's result.
Simply put
An auditor cannot examine thousands of invoices one by one, so he selects a sample in a planned way, statistically or by professional judgment, focusing on large and risky items.
The weaker the internal control, the larger the sample, because the likelihood of error is higher.
Worked example
A spare parts store issued 5,000 sales invoices during the year, and the auditor decided to examine a sample of 200 invoices.
Number of invoices in the year5,000
Sample size200
Sample percentage200 ÷ 5,000 = 4%
Share of invoices the auditor actually examines4%
Formula: Sample percentage = sample size ÷ number of items in the population
Don't confuse it with
Complete auditA complete audit does not use samples at all.