High Quality Content by WIKIPEDIA articles! A concept inventory is a criterion-referenced test designed to evaluate whether a student has an accurate working knowledge of a specific set of concepts. To ensure interpretability, it is common to have multiple items that address a single idea. Typically, concept inventories are organized as multiple-choice tests in order to ensure that they are scored in a reproducible manner, a feature that also facilitates administration in large classes. Unlike a typical, teacher-made multiple-choice test, questions and response choices on concept inventories are the subject of extensive research. The aims of the research include ascertaining (a) the range of what individuals think a particular question is asking and (b) the most common responses to the questions. Concept inventories are evaluated to ensure test reliability and validity. In its final form, each question includes one correct answer and several distractors. The distractors are incorrect answers that are usually (but not always) based on students` commonly held misconceptions.