Transcript TDG Report Illness scripts for improving clinical reasoning

TDG Report
Illness scripts for improving clinical reasoning
Anna Lee, Tony Gin, Charles Gomersall,
Warwick Ngan Kee, Gavin Joynt, Anthony Ho,
Juliana Chan, Lex Vlantis, James Griffith,
William Wong, Coleman Fung
Clinical reasoning

Involves solving medical problems in
order to make decisions about a
patient’s diagnosis and management
Groves 2002
Key elements of the clinical diagnostic process
Knowledge
Patient’s story
Data acquisition
Accurate “problem representation”
Context
Generation of hypothesis
Search for and selection of illness script
Experience
Diagnosis
Bowen JL. NEJM 2006;355:2219
Development of Medical Expertise and
clinical reasoning
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Stage 1. Development of elaborate
causal networks
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Learned during basic science years
Recall facts or explain causal models of
disease processes
Driving a car = “This is the steering wheel and it………This is the
brake pedal……..This is a roundabout, and at roundabouts you have
to…….”
Schmidt et al. Acad Med 1990;65:611-21
Stage 2. Compilation of abridged
networks
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Starts when exposed to real patients
Knowledge gets compiled (rewritten,
automated)
“Diagnosing a first clinical case requires quite a lot of mental effort and
involves extensive reasoning based on the elaborate causal networks
available to the student, but when he sees his second or third similar
case, shortcuts will emerge. He will no longer have to activate all possibly
relevant knowledge in order to understand what is going on in his patient;
only knowledge pertinent to understanding the case will be activated“
Remember the first time you got in a car and drove?
Schmidt et al. Acad Med 1990;65:611-21
Stage 3. Emergence of Illness scripts
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Based on repeated experience with
patients
Illness scripts are sufficient to diagnose
and treat diseases
OK, you passed the driving test. Are you likely to be over
confident? Can you assess risks quickly and accurately?
Schmidt et al. Acad Med 1990;65:611-21
Illness scripts
Enabling Conditions
Eg. Being male, older, smoking
Fault
Eg. Myocardial infarction
Consequences
Eg. Profuse sweating, SOB, severe
and radiating chest pain
Van Schaik et al. J Exp Psychol 2005;11:187-99
Stage 4. Storing patient encounters as
instance scripts

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
Based on long experience
Physician remembers many individual
patients but each has a different variant of
the disease
New (or newly sick) patients are


recognized as “similar to Patient X”
treated as Patient X was treated
Now you’ve been driving for years. Are you sure you are up to date
with the highway code? And technically, are you sure you have picked
up all good habits (shortcuts), and no bad habits?
Schmidt et al. Acad Med 1990;65:611-21
Project objectives
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
To develop and implement a teaching
module to improve 4th year medical
students’ clinical reasoning skills
To assess students’ level of clinical
reasoning skills
Teaching intervention
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Rotation to 4th year Family Medicine
module
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Short lecture on clinical reasoning and
illness script theory (0.5h)
Small group work on “problem
representation” (1.5h)
Individual guided computer work using
clinical reasoning scenarios (1.5h)
Example of clinical reasoning problem
•Pull down menus
Key elements of the clinical diagnostic process
Knowledge
Patient’s story
Data acquisition
Accurate “problem representation”
Context
Generation of hypothesis
Search for and selection of illness script
Experience
Diagnosis
Bowen JL. NEJM 2006;355:2219
Assessment of clinical reasoning (1)
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Diagnostic Thinking Inventory
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Flexibility in thinking
Structure of knowledge in memory
CUHK teachers (n=7)
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Flexibility in thinking (77%)
Structure of knowledge in memory (78%)
Bordage et al. Med Educ 1990;24:413-25
Assessment of clinical reasoning (2)
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Clinical reasoning problems
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Different set of scenarios
Students type their answers/cut and past
key features from scenarios (spell-check
features)
Scores given to correct diagnoses and key
features
Assessing students’ learning outcome
Students
Begin rotation
Teaching package End of rotation
Intervention Diagnostic
Thinking
Inventory
(25 min online)
Clinical reasoning
Diagnostic Thinking
Inventory + clinical
reasoning scenarios on web
(2 hours)
Control
Self-directed
learning
Diagnostic Thinking
Inventory + clinical
reasoning scenarios on web
(2 hours)
Diagnostic
Thinking
Inventory
(25 min online)