Clinical Reasoning and Illness Scripts Flashcards
Why are illness scripts important?
Why are scripts important?
They…
1. Enable pattern recognition of epidemiological features.3
2. Inform history taking based on the contextual
patterns identified.3
3. Enhance the integration of new clinical knowledge
with prior knowledge.3
4. Improve diagnostic efficiency and accuracy.3
How do physicians build illness scripts at the novice level, at the intermediate level, and at the expert level?
HOW DO PHYSICIANS BECOME EXPERTS?
THEY BUILD ILLNESS SCRIPTS
At the novice level, they rely on biomedical knowledge
to explain disease.
At the intermediate level, they organize biomedical
knowledge using signs and symptoms to explain disease.
At the expert level, they create a narrative framework of
clinical features to rule in or rule out differential diagnoses.
List and describe the 4 components most commonly included in illness scripts
a. Epidemiology
b. Temporal course
c. Pathophysiology
d. Clinical presentation
What is an illness script?
Illness scripts are mental cue cards used to represent
individual diseases.
How are experts’ illness scripts different than a novice illness script?
When expert physicians encounter a case, they quickly retrieve appropriate illness scripts from their long-term memory to create a differential diagnosis.
In contrast to a novice’s illness script, which is overflowing with detailed biomedical knowledge, the expert’s illness script consists of highly organized cues derived
from clinical features. In difficult cases, experts weigh biomedical knowledge, laboratory findings, and imaging data to further refine the differential and to determine management. Experts elaborate upon illness scripts by adding atypical disease presentations over time.
What would be the illness script for appendicitis?
ILLNESS SCRIPT FEATURES FOR
ACUTE APPENDICITIS
1. Epidemiological factors
Gender: men = women; Age: peak incidence 10–30
years old; Risk factors: lymphoid hyperplasia
2. Signs and symptoms of disease
Vague, unprovoked periumbilical pain that gradually
becomes intense; severe, right lower quadrant pain.
Pain is associated with loss of appetite, fever, and
vomiting. Pain improves with narcotics.
3. Pathophysiology
Appendix obstruction from appendicolith, carcinoid
tumor, or lymphoid hyperplasia. Inflamed appendix
may cause peritoneal signs (e.g., Rovsing’s sign).
What is anchoring bias? What is a corrective strategy for this?
Sticking with a diagnosis
Ex:
Continuing to treat a ring-like lesion with antifungals, and the lesion turns out to be discoid lupus erythematosus
Corrective strategy:
Examine the impact of nonresponse or new information on the original diagnosis
What is availability bias? What is a corrective strategy for this?
Referring to what comes to mind most easily
Making a diagnosis based on a previous patient with similar symptoms
Corrective strategy:
Know baseline prevalence and statistical likelihoods of the condition diagnosed
What is confirmation bias? What is a corrective strategy for this?
Assigning preference to findings that confirm a diagnosis or strategy
Concluding that leukocyte esterase present on urine dipstick testing in a patient with back pain confirms the patient’s self-diagnosis of kidney infection
Corrective strategy:
Use an objective source (e.g., differential diagnosis checklist, a review of pyelonephritis) to evaluate whether the diagnosis correlates with technical findings
What is framing bias? What is a corrective strategy for this?
Assembling elements that support a diagnosis
Assuming that symptoms are malarial in a patient who recently returned from Africa
Corrective strategy:
Elicit different perspectives by broadening the history to search for other causes or associations
What is premature closure bias? What is a corrective strategy for this?
Failing to seek additional information after reaching a diagnostic conclusion
Failing to note a second fracture after the first has been identified
Corrective strategy:
Review the case, seek other opinions (e.g., radiology backup), and consult objective resources (e.g., an orthopedic review that might include mention of a common concomitant fracture)
