In our day-to-day work as a GP, we undertake clinical reasoning with nearly every patient, mostly subconsciously. However, in preparation for the KFP exam, it can be helpful to deconstruct the clinical reasoning process. Hence this blog!
The ultimate goal, however, is to make us better clinicians, not just to pass the exam!
One definition of clinical reasoning is the ability to integrate and apply knowledge, to weigh evidence, to critically think about arguments, and to reflect upon the process used to arrive at a diagnosis. We learn this from observation of our consultants and supervisors, reflection and practice. The definition implies that we have a good knowledge of medicine, and the conditions that we encounter.
We should have an ‘illness script’ for each condition, so that we can compare it to the bank of other conditions in our mental ‘filing cabinet (pattern recognition). An illness script for a condition should include a disease's pathophysiology, epidemiology, time course, salient symptoms and signs, diagnostics, and treatment.
Dual Process Theory
It is important to know about dual process theory when we are talking about clinical reasoning.
As medical students, we are taught type 2 thinking. This is the slow, methodical, logical, process-driven type of thinking, where we take a history from the patient, formulate a differential diagnoses, and rule those differentials in or out by further history, physical examination and investigations.
In comparison, Type 1 thinking is intuitive, fast, automatic and experiential. This is developed as we become more experienced. The non-analytic approach is more common, accounting for 80% of clinical reasoning and is based on pattern (or illness script) recognition.
A good clinical thinker routinely approaches a clinical presentation by using a combination of type 1 and type 2 thinking. When presented with an adolescent with a headache, fever and petechial rash, for example, the type 1 thinker in us will immediately jump to meningococcal sepsis. However, we need to go through the process of type 2 thinking to make sure that we haven’t missed something else, such as infectious mononucleosis, tonsillitis, or leukaemia.
Preparing for the KFP
When preparing for the KFP, be aware of which type of thinking you are predominantly using. It is important to see as many patients as possible in the lead up to the exam and use them to practice your clinical reasoning. Practice your type 2 reasoning and use a diagnostic framework to do this.
Using a diagnostic framework will decrease the number of errors that you make and ensure that you use your type 2 thinking when asked for differential diagnoses. There are several diagnostic frameworks that you can use, such as Murtagh’s PROMPT, VINDICATE or VITAMINCDE, or an anatomical or pathological framework. I tend to use both PROMPT and VINDICATE when I am stumped or want to be sure that I am not missing anything.
In the lead up to the exams, I would suggest that you use a diagnostic framework with every patient you see who presents with a new problem. If you do this, you will become more proficient at using this skill.
Any history questions, physical examination and investigations should be targeted at ruling in and ruling out your differentials and red flags. The 'Masquerades' and 'Often Missed' in PROMPT should be thought of and investigated if appropriate.
There are two very important strategies that cannot be underestimated, both in the real clinical situation, and in the exams.
- Take a ‘diagnostic pause’. If you are not sure what is going on, just stop, and think! If you are with a patient, send them out for a urine sample, take their blood pressure and sit in silence, or get up and wash your hands. Any one of these strategies is a perfectly legitimate way to give you a minute to think!
- Ask yourself ‘Is there anything else that this could be?’ This is one of the most important questions that you can ask in medicine! Also consider the following – ‘Have I rushed into this diagnosis?’, ‘Have I just relied on my type 1 thinking?’, ‘Could this be anything serious?’, ‘Could it be one of Murtagh’s red flags (metabolic, malignancy, infection, infarction)’. If the answer is no – then move on.
There are several good resources to help improve your clinical reasoning.
- Being aware of diagnostic error is important. This article on Life in the Fastlane is helpful.
- The IM Reasoning podcast series is very helpful, particularly the ‘Stump the Chumps’ episodes. Especially if you do a lot of driving or walking! They can be downloaded from App store, or found at IM Reasoning
- An AFP article on learning Clinical Reasoning
- The Society to Improve Diagnosis in Medicine has a website, with a Clinical Reasoning Toolkit, with several resources. If you are interested in reading more about this area, I suggest that you look at this.
To learn more about clinical reasoning, and how to apply this knowledge through the prism of minimising diagnostic error, Medcast are running a brand new webinar series called ‘Not to be missed’, commencing on Thursday February 10. Delivered as a series of bite-sized clinical cases, we will explore uncertainty, bias and reasoning, as well as core clinical knowledge based on the international literature.