Skip to content

Audit and Assurance · Audit sampling and other means of testing

Selecting Items for Testing Without Sampling in Audit

Updated 11 October 2026 · Fact-checked

Under ISA 500 an auditor has three means of selecting items for testing: select all items (100% examination), select specific items, or use audit sampling. The choice depends on the risk, the population and the efficiency of each option. Only sampling lets you draw conclusions about the whole population.

Understand Selecting Items for Testing Without Sampling

When you test a balance or a class of transactions, you must decide which items to look at. You cannot always look at everything, and you should not always pick at random. ISA 500 gives three means of selecting items for testing.

Selecting all items (100% examination) means you test every item in the population. It suits populations with a small number of large-value items. It also suits cases where there is a significant risk and other methods will not give enough evidence. It can suit repetitive calculations that a computer can check cheaply, for example recalculating every line of a depreciation schedule using audit software.

Selecting specific items means you choose items using your judgement. You might pick all items above a set value (key items), all unusual or high-risk items, items that give you information about the client, or items that test a control procedure. Examples are large or old receivables, journals posted by senior management, or items near the year end. The result is not a sample in the ISA 530 sense. You cannot project your findings to the whole population. Any remaining items still need other work if they could be material in total.

Audit sampling means applying procedures to fewer than 100% of items so that every item has a chance of selection. You then draw a conclusion about the whole population. It suits large populations of similar, lower-value items where 100% testing would be too costly.

The three are not exclusive. A common approach is to test all items above a threshold, then sample from the rest. The key exam skill is matching the method to the facts: risk, number of items, value spread and cost.

Key rules to remember

Three means of selection (ISA 500)
Select all items | Select specific items | Audit sampling
Learn the names exactly. Auditors may use any one or a combination, depending on the circumstances.
When 100% examination suits
Few items + high value, OR significant risk, OR cheap automated check
Typical triggers: small population of large items, significant risk where other evidence is not enough, or recalculation by software.
When specific items suit
Key items, high-risk or unusual items, items to gain information, items to test a control
Results apply only to the items tested. You cannot extrapolate to the rest of the population.
When sampling suits
Large population + similar items + conclusion about the whole population needed
Every item must have a chance of selection. Sampling risk exists and results can be projected.

How to solve Selecting Items for Testing Without Sampling questions

Use this method for any question asking how an auditor should select items or why a method was chosen.

  1. 1Identify the population: what is being tested, how many items, and the range of values.
  2. 2Identify the risk: is there a significant risk, fraud risk, or an unusual or related-party item?
  3. 3Check the numbers: a few large items point to 100% or specific items; many small similar items point to sampling.
  4. 4Consider cost and practicality: could software test every item cheaply? Would manual testing of all items be too slow?
  5. 5Choose the method or combination, for example test all items above a value, then sample the rest.
  6. 6State what the result lets you conclude: only about the items tested for 100% and specific items; about the whole population for sampling.
  7. 7Say what you do about the untested remainder if it could be material in total.

Quickest way: Risk, size, conclusion

When to use it: Use when you have little time in a Section A or OT case question asking which selection method is most appropriate.

  1. Ask: do I need a conclusion about the whole population? If yes, only sampling gives it.
  2. Ask: are there few, large or high-risk items? If yes, choose 100% or specific items.
  3. Ask: can software check every item cheaply? If yes, 100% is reasonable.
  4. Remove any option that claims specific items can be projected to the whole population.

Common mistakes in Selecting Items for Testing Without Sampling

  • Treating specific item selection as a type of sampling.

    Both involve testing fewer than all items, so they look similar.

    Fix: Remember that sampling gives every item a chance of selection. Specific items are chosen by judgement, so you cannot project the results.

  • Saying 100% examination is always the most reliable and so always best.

    Testing everything sounds thorough.

    Fix: Say it is suited to small populations, significant risks or automated checks. For large populations it is usually uneconomic.

  • Projecting errors found in specific items to the whole population.

    Students apply sampling logic to every test.

    Fix: State that errors in specific items are reported for those items only. Consider other work on the remainder.

  • Ignoring the untested items after selecting key items.

    Students assume the large items cover everything.

    Fix: Check whether the remainder could be material in total. If so, sample it or use analytical procedures.

  • Giving a generic answer without using the scenario facts.

    Students recall a list but do not apply it.

    Fix: Quote numbers, values and risks from the scenario, then link each to your chosen method.

Worked examples

Example 1

An audit client has 12 long-term loan agreements totalling $48 million. Materiality is $600,000. Explain which means of selecting items the auditor should use to test the loan balance.

Show the solution
  1. The population is small: only 12 items.
  2. The items are individually large and in total far exceed materiality.
  3. Testing all 12 is practical and gives the strongest evidence.
  4. Sampling would add sampling risk with little saving in effort.

Answer: Select all items (100% examination). With only 12 large loans, testing every one is efficient and avoids sampling risk.

Example 2

An auditor tests 8,000 sales invoices. Forty invoices exceed $50,000 and make up 55% of total sales value. The rest are small and similar. Recommend how to select items and explain what conclusions can be drawn.

Show the solution
  1. The 40 large invoices cover over half the value, so test all of them as key items.
  2. This is a form of selecting specific items (or all items in that stratum). Results cover only those 40.
  3. The remaining 7,960 invoices are many, similar and low in value.
  4. Use audit sampling on these, so each has a chance of selection.
  5. Sampling results can be projected to the remaining invoices; results for the 40 apply only to them.

Answer: Test all 40 invoices above $50,000, then sample from the remaining 7,960 invoices. Conclusions on the large invoices apply only to them, while sample results can be projected to the small invoices.

Exam tips

  • Name the three means exactly as ISA 500 does, then link your choice to the scenario facts.
  • If a question asks what conclusion you can draw, say specific items cannot be projected, but sampling can.
  • In OT questions, eliminate options that say specific items give a conclusion on the whole population.
  • In Section C, use a combined approach if the scenario shows a few large items and many small ones, and say why.

Selecting Items for Testing Without Sampling: frequently asked questions

What are the three means of selecting items for testing?

They are selecting all items, selecting specific items and audit sampling. These come from ISA 500. The auditor chooses based on risk, population size and efficiency, and may combine them.

When should an auditor test all items instead of sampling?

Test all items when the population has few large items, when there is a significant risk and other methods will not give enough evidence, or when software can check every item cheaply. Otherwise sampling is usually more efficient.

Is selecting specific items the same as sampling?

No. In sampling, every item has a chance of selection and you can project the result. Specific items are chosen by judgement, so the result applies only to those items.

Can I use more than one method on the same balance?

Yes. A common approach is to test all items above a value, then sample the rest. You may also add analytical procedures on the remainder.