This procedure raises concerns about respondent fatigue and item difficulty.

Using this tool teachers can search for exemplar questions by content, item type (i.e., multiple choice or constructed response), or item difficulty.

But to test, for example, the assumption about item difficulty being independent of the student requires assuming that ability is unidimensional; in other words it cannot be tested!

Both of these ideas contravene the model, which assumes that item difficulty is invariant under these conditions.

In this special case, the item difficulty and (single) threshold are identical.

SMEs sort test items into categories of appropriate difficulty, or correlate item difficulty to course levels.

One and the same scale is used to express item difficulties and student competences.

The parameter represents the item location which, in the case of attainment testing, is referred to as the item difficulty.

The P-value represents the proportion of examinees responding in the keyed direction, and is typically referred to as item difficulty.

Among other things, this meant that the sequence of item difficulties must be the same for persons of all levels of ability.