Essay tests allow for the assessment of higher-order thinking skills as they are classified as non-objective tests. In an essay test, students are requested to write one or more paragraphs on a specified topic to organize their thoughts and inform an audience. Stecklein identified 14 types of abilities that can be measured by essay items, including comparisons, development and defense of opinions, explanations, summaries, analysis, knowledge of relationships, and inferential thinking. When grading essay papers, rules of thumb include phrasing the directions to guide students on key concepts and informing students of the criteria that will be used, such as coherence, accuracy, use of keywords, and clarity.