A concept inventory is a criterion-referenced test designed to help determine whether a student has an accurate working knowledge of a specific set of concepts. Historically, concept inventories have been in the form of multiple-choice tests in order to aid interpretability and facilitate administration in large classes. Unlike a typical, teacher-authored 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.
Ideally, a score on a criterion-referenced test reflects the degrees of proficiency of the test taker with one or more KSAs (knowledge, skills and/abilities), and may report results with one unidimensional score and/or multiple sub-scores. Criterion-referenced tests differ from norm-referenced tests in that (in theory) the former report level of proficiency relative pre-determined level and the latter reports relative standing to other test takers. Criterion-referenced tests may be used to determine whether a student reached predetermined levels of proficiency (i.e., scoring above some cutoff score) and therefore move on to the next unit or level of study.
The distractors are incorrect or irrelevant answers that are usually (but not always) based on students' commonly held misconceptions.[1] Test developers often research student misconceptions by examining students' responses to open-ended essay questions and conducting "think-aloud" interviews with students. The distractors chosen by students help researchers understand student thinking and give instructors insights into students' prior knowledge (and, sometimes, firmly held beliefs). This foundation in research underlies instrument construction and design, and plays a role in helping educators obtain clues about students' ideas, scientific misconceptions, and didaskalogenic ("teacher-induced" or "teaching-induced") confusions and conceptual lacunae that interfere with learning.