One of the most widely influential models of skills acquisition was introduced by two brothers from Terre Haute, Indiana, both of whom later joined the faculty of the University of California, Berkeley. Hubert Dreyfus, who passed away in April of 2017, was not only a professor of philosophy and an expert on the German philosopher Martin Heidegger, but he also made important contributions to the understanding of artificial intelligence. Stuart Dreyfus completed a PhD in applied mathematics and helped to advance the field of computer programming; he is now a professor emeritus of industrial engineering and operations research at Berkeley. Together, the Dreyfus brothers, who were on contract to the US Air Force, co-authored in 1980 an 18-page report detailing the role of formal instruction and practice in skills acquisition , which they subsequently developed in their 2000 book entitled Mind Over Machine .
Five Stages
The original Dreyfus skills acquisition model consisted of five stages, to which they later added a sixth. Although it is primarily the final and highest stage on which we wish to focus in this article, it is important first to review each of the first five stages. The first stage is novice. At this stage, learners lack any experience for recognizing the context in which they operate, and they function strictly by rules. For example, a novice at chest radiograph interpretation might be taught to use the cardiothoracic ratio to assess for cardiomegaly, according to the rule that a cardiothoracic ratio over 0.5 is abnormal, without any understanding of processes such as pericardial effusion that can mimic cardiomegaly or any appreciation for the differential diagnosis of such a finding. Hence, novices should be evaluated largely by whether they know and follow the rules.
The second stage of the Dreyfus model of skills acquisition, which the authors added later, is advanced beginner. At this stage, learners can begin to perceive features of the situation in which they find themselves and are no longer blindly applying rules. However, they are unable to distinguish between the relative importance of these different features and tend to treat them all as equally significant. For example, students of radiology might learn to assess not only heart size but also opacities in the lungs, pleural effusions, and the presence or absence of pneumothorax, thereby beginning to produce a comprehensive report. However, they are unable to determine which of these findings might be of more importance than another, and they cannot combine the findings into a meaningful overall assessment, such as a diagnosis of congestive heart failure.
The third stage of the Dreyfus model is competence. As learners develop competence, they learn to apply guidelines to features of the situation in which they find themselves. At this level, learners are able to follow these guidelines to determine what rules to follow in different situations. For example, a student of chest radiography might learn that the cardiothoracic ratio is helpful only in cases where the patient is upright, the lungs are well inflated, and a posteroanterior radiograph is obtained. Before measuring the cardiothoracic ratio, such learners would inspect a radiograph to determine whether it met these criteria and then follow the appropriate guideline for determining whether to apply the rule. Only at this level can learners be said to have a meaningful practical sense of what they are actually doing.
The fourth stage is proficiency. At this stage, learners are able to perform appropriately in a wide variety of real-world situations, and they understand how what they are doing is contributing to the achievement of a long-term goal, such as diagnosing disease and restoring health. They can also determine which aspects of the situation are more or less relevant to the achievement of this goal. Proficient radiology learners can dictate a whole chest radiograph report, arranging its elements to provide the referring physician with an ordered set of findings, conclusions, and recommendations. If some aspects of the situation change, such as the patient’s age or underlying medical condition, the proficient learner can respond appropriately, modifying the approach to meet the demands of the particular situation at hand.
The fifth stage is expertise. Up to this point, learners have been operating with a principle, such as a rule, guideline, or maxim to guide their performance in connecting the general aspects of knowledge to the particular situation. At the level of expertise, however, learners have become so experienced that they are able to diagnose the situation and respond appropriately to it on an intuitive basis. Radiologists are functioning not by following algorithms but through pattern recognition, and different kinds of patterns are intimately linked to different kinds of responses. Radiology experts can largely dispense with search patterns and mnemonics and simply know what they are seeing when they see it. This is not to say that experts cannot be stumped or that they never fall back on principles, but such situations are significant precisely because they are exceptional.
The Sixth Stage
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References
1. Dreyfus S., Dreyfus H.: A five-stage model of the mental activities involved in directed skills acquisition.1980.Storming MediaWashington, DC Available at https://www.cmqcc.org/resource/1065/download
2. Dreyfus S., Dreyfus H., Athanasiou T.: Mind over machine.2000.Simon and SchusterNew York
3. Batalden P., Leach D., Swing S., et. al.: General competencies and accreditation in graduate medical education: an antidote to over-specification in the education of medical specialists. Health Aff 2002; 21: pp. 103-111.