I was recently made aware of the fascinating book ‘How Doctors Think’ by Jerome Groopman. Groopman, an oncologist in Boston, Chair of Medicine at Harvard Medical School and a staff writer for the New Yorker, is in an ideal position to both provide insight into the topic and write about it in an accessible way.
As always there are many interesting themes in the book, several of which are directly applicable to veterinary practice and education. This will be the first of (probably!) three posts, each covering different topics.
One of the ideas introduced early in the book was the concept of heuristics, defined in Wikipedia as ‘experience-based techniques for problem solving, learning, and discovery that gives a solution which is not guaranteed to be optimal. Where the exhaustive search is impractical, heuristic methods are used to speed up the process of finding a satisfactory solution via mental shortcuts to ease the cognitive load of making a decision.’ 1We all use these in everyday life, learning to ignore information that is extraneous to our needs at a given moment. For example, if waiting for a car to pass while crossing the road, we may not pay attention to the colour of the car but will be absolutely aware of when it has passed and we can safely cross. Heuristics have a clear application to clinical decision making, most obviously in an emergency situation but also in many other scenarios.
Heuristics can be personal and very specific to a diagnostic process in a particular environment or general with application across many disciplines. An example of the former could be a young dog presented for coughing but generally bright and alert, recently been in contact with other dogs and not yet fully vaccinated. As soon as I set eyes on that patient across the waiting room I have kennel cough in mind as a likely diagnosis, even though I have not fully examined the dog and have no objective data. Another name for this type of thinking is pattern recognition. A more general diagnostic heuristic could be the oft-repeated phrase, ‘If you hear hoof beats, think of horses, not zebras’ ie look for a common disease process before chasing the possibility of a rare cause.
When utilized by experienced clinicians, there is considerable evidence that heuristics are a powerful means of providing high-quality care in an efficient manner in the face of clinical uncertainty2. Pat Croskerry, an emergency doctor who studies physician cognition, calls heuristics ‘the essential tools of clinical medicine’ 3 and I certainly know I’ve employed them in many a case, despite having no specific instruction in their development and use, a situation I share with Groopman who notes in the boo that shortcuts were not taught to him in medical school. Clement McDonald in his 1996 article stated that ‘the heuristics of medicine should be discussed, criticized, refined and then taught. More uniform use of explicit and better heuristics could lead to less practice variation and more efficient … care.’4
Wegwarth et al assert that ‘Today’s medical students should learn and understand that heuristics are neither good nor bad per se, but that their reliability and usefulness interplays with environmental circumstances, such as the inherent uncertainty of a specific situation. To broaden students’ knowledge of what kind of environmental circumstances can be exploited in what fashion by what heuristic mechanisms seems as crucial as to teach them the building blocks from which heuristics can be constructed and adjusted for other problems or populations.’ 5 I certainly agree the concept should be introduced to veterinary students. I’d be very interested to hear from any veterinary educators about whether and how you are teaching heuristics.
Having discussed the obvious advantages of heuristics above, there are some significant caveats to using heuristics as, somewhat ironically, they are also a major source of diagnostic error, the topic of my next post.
- Wikipedia http://en.wikipedia.org/wiki/Heuristics Retrieved 12 August 2013
- 2Kempainen Robert R., Migeon Mary B. and Wolf, Fredric M., 2003. Understanding our mistakes: a primer on errors in clinical reasoning. Medical teacher, 25(2), pp.177–181. Available at: https://childrenshospital.org/cfapps/research/data_admin/Site2275/securepages/Documents/ClinicalReasoning.pdf.
- Croskerry, P., 2003. Cognitive forcing strategies in Clinical Decision making. Annals of Emergency Medicine, 41, pp.110–120.
- McDonald, C., 1996. Medical heuristics: the silent adjudicators of clinical practice. Annals of Internal Medicine, 124(1), pp.56–62.
- Wegwarth, O., Gaissmaier, W. & Gigerenzer, G., 2009. Smart strategies for doctors and doctors-in-training: heuristics in medicine. Medical Education, 43, pp.721–728.