Introduction

Benjamin Bloom and colleagues developed the Taxonomy of educational objectives: the cognitive domain in 1956, which serves as the foundation for educational objectives and learning goals.  Bloom’s taxonomy created a common language such that learning materials could be compared between institutions and provided a way to assess what a curriculum offered within the learning domain.  The three learning domains are cognitive, affective, and psychomotor.  Bloom’s taxonomy published in 1956 is specific to the cognitive domain and presents a hierarchical structure with six levels of learning: knowledge (lowest level), comprehension, application, analysis, synthesis, and evaluation (highest level).  Bloom’s taxonomy was revised in 2001 by Lorin Anderson and David Krathwohl (one of the authors of the original taxonomy).  Regarding this revision, Krathwohl commented on how Bloom’s taxonomy went from a unidimensional ladder of cognitive processes to a two-dimensional structure of cognitive processes and types of knowledge.  The knowledge dimension consisted of factual knowledge, conceptual knowledge, procedural knowledge, and metacognitive knowledge subtypes. The dimension of cognitive processes resembled the original taxonomy, with six levels:  remember, understand, apply, analyze, evaluate, and create. The names of the levels were changed from nouns to verbs, and the highest level became “create.”[1]

Since Bloom’s taxonomy for the cognitive domain, additional taxonomies have been created both for the cognitive domain and for the affective and psychomotor domains.  New taxonomies will continue to be designed to fit wider educational needs.  One example of another taxonomy is Fink’s Taxonomy of Significant Learning, which consists of six parts: learning how to learn, foundational knowledge, application, integration, human dimension, and caring.[2]

These taxonomies can be useful to help guide the creation of curriculum learning objectives and to reveal what a curriculum might be lacking. Often in medical education, learning objectives focus on knowledge more than the other domains.[3] The field of medical simulation comprises a variety of educational tools and approaches that can reach learning objectives across all three educational domains. 

Curriculum Development

Educational taxonomies, including Bloom's, can be used to develop educational objectives for a curriculum, as well as identify pieces that may be missing from an existing curriculum. Bloom's taxonomies are often presented with examples of verbs corresponding to each level, which can aid in identifying where a learning objective fits in the taxonomy. The revised taxonomy can be presented in a 4x6 table with knowledge and cognitive processes axes.  In the revised taxonomy, there are four kinds of knowledge: factual, conceptual, procedural, and metacognitive. Examples of factual knowledge are knowledge of terminology and specific details.  Knowledge of classifications, categories, principles, and theories are examples of conceptual knowledge.  Knowledge of subject-specific skills and techniques are examples of procedural knowledge.  Finally, metacognitive knowledge includes knowledge about one's self and knowledge about cognition. Considering these different types of knowledge against cognitive processes can help create learning objectives that move beyond recalling factual knowledge.[4] 

Often, curricula over-emphasize the lower levels of Bloom's taxonomy and knowledge subtypes. Zheng et al. were able to apply Bloom's taxonomy to show how first-year medical school courses in biology have exam questions focused on the knowledge/comprehension/application levels of learning, whereas the MCAT had more high-level questions.[5] The art of medicine encompasses more than knowledge regurgitation, and using learning taxonomies can ensure that a curriculum moves learners beyond just remembering and recalling. Furthermore, aside from needing to function at higher levels in the cognitive domain, medicine calls for both emotional intelligence and fine motor abilities.  

Simulation can incorporate the full breadth of educational opportunities as learners are placed into seemingly real-life scenarios. Therefore, all three learning domains of cognitive, affective, and psychomotor should be considered when designing a simulation scenario for medical education.[6] For example, a cognitive domain objective could be having the learner demonstrate proper calculations to get a particular drug concentration. An objective to show adequate communication with other team members would be in the affective domain. An objective to show how to draw up a medication properly would fall into the psychomotor domain.[7] Therefore when creating a simulation, one can consider learning objectives beyond the traditional Bloom's taxonomy, and in turn, encompass the full breadth of educational opportunity.

Taxonomies can be used to facilitate communication across institutions about learning materials. Many educational taxonomies have been created since the original Bloom's Taxonomy in 1956, and more continue to be developed.  For example, in a multi-center trial, McIvor et al. showed how creating a new taxonomy could allow a comparison of how different simulation centers executed a standardized simulation.[8] This article demonstrates how new taxonomies can be developed as needed to fill an educational gap. 

Procedural Skills Assessment

In medicine, teaching motor skills is incredibly important, so learners are competent in performing procedures. Using the affective and psychomotor learning domains in conjunction with the cognitive domain can help improve curriculums for procedural-based specialties.[9] For example, for creating a simulation for a surgical specialty, it might be useful to use Dave's psychomotor taxonomy (imitation, manipulation, practical precision, articulation, and naturalization) to help develop relevant learning objectives.[10]  Another taxonomy that has been devised for the psychomotor domain is Simpson's taxonomy, which presents seven categories: perception, set, guided response, mechanism, complex overt response, adaptation, and origination.[6]

Clinical Significance

Medical simulation provides a way to integrate multiple levels of the learning taxonomies across the learning domains, which in turn can help improve training and clinical outcomes. For example, Chan et al. demonstrate a pedagogy that moves beyond the cognitive domain and includes affective elements with the use of standardized patients.[11]

Enhancing Healthcare Team Outcomes

Healthcare team training has been demonstrated to improve patient outcomes.[12] Furthermore, simulation can be used to teach ethics and place learners in scenarios where they must align their actions with their values.[13] The affective learning domain encompasses communication and teamwork and therefore, can help create learning objectives designed to improve healthcare teams.  Krathwohl presented a taxonomy for the affective domain with five levels: receiving, responding, valuing, organization, and characterization by a value or value complex.[6] Incorporating learning objectives from the affective domain in addition to those from the cognitive domain can create a more complete and encompassing simulation scenario, and drive beneficial results for students' outcomes.