What is the p-value of a question?

What exactly is the p-value of a question? Converted into a percentage (* 100), the p-value indicates the percentage of candidates that answered the item correctly. If you have a high p-value, the question is relatively easy and almost every candidate got it right. If you have a low p-value, the question has been too difficult. In that case the proportion of candidates who got the question right is too low.

What is a good p-value?

If you want to make a good test, you have to make sure there is a good balance between the question types. A test should not be too difficult, but also not too easy. A good p-value varies according to the number of answer possibilities. You can use the table below as a guideline:

Optimal p-values for different types of questions

Calculating the p-value of a question

Suppose you have a question in your test that is answered by 100 students. You perform a statistical analysis by calculating the number of correct answers. Suppose 60% of the candidates get the question right, then there is a p-value of 0.60.

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