Each of the six levels in the hierarchy provides an essential skill for students who would like to write cognitively advanced literature reviews. Applied to the process of writing, each level provides a critical component of the process. The levels are articulated in the following sections, with descriptions based on those included in the Learning Skills Program (1999) and with appropriate applications made to the writing process. Of course, it should be recognized that an individual paper may not fit neatly into only one category on the Taxonomy. Nevertheless, the paper can be classified generally into a Taxonomy level based on the overarching principle used to organize and write it, and a precise categorization of the entire paper is not necessary for this method to be successful in promoting cognitive advancement.

Knowledge. In this lowest level, the student recalls or recognizes information, ideas, and principles in the approximate form in which they were learned. The material may vary from specific facts to complete theories, but all that is required is remembering the information. Students who use only this cognitive level in their writing will simply repeat information from other sources without demonstrating an understanding of the material or making distinctions between the quality of the different sources. Common assumptions made by writers at the knowledge level include the following: If it has been published, it is worthy of inclusion; all published articles are equally valid; no true distinctions can be drawn between research and nonresearch articles; and main ideas from source material cannot be distinguished from less important ideas presented.