Supplementary Table 3. Common cognitive biases and flaws in SLE diagnosis and management
Step in diagnosis
Bias
Definition
Example
Development of
differential diagnosis
Availability recall
Referring to what comes to mind most
easily. Differential influenced by what
is easily recalled, creating a false sense
of increased prevalence of the condition
Influenced by a recent case of sagittal sinus thrombosis in
a patient with SLE headache, clinician thinks of venous
thrombosis in subsequent SLE patients with headache,
neglecting more common causes such as migraine
Representativeness
(Judging by similarity)
Clinical suspicion influenced solely by
signs and symptoms, and neglects to
consider competing diagnoses
A young woman with low grade fever, malaise, arthralgias
and myalgias interpreted as SLE flare rather than as a viral
illness
Confirmation (pseudodiagnosticity)
Assigning preference to findings that
confirm a diagnosis or strategy.
Additional testing confirms suspected
diagnosis but fails to test competing
hypotheses
Acute onset of pleuritic chest pain in a woman with SLE
and antiphospholipid antibodies with a small pleural
effusion interpreted as pleurisy without testing for
pulmonary embolism
Anchoring and
adjustment
Sticking with a diagnosis. Inadequate
adjustment of differential in light of
new data results in a final diagnosis
unduly influenced by initial impression
Nephritis in a patient with positive ANA and rheumatoid
factor.
Framing (bounded
rationality)
Assembling elements that support a
diagnosis. Clinician stops search for
additional diagnoses after anticipated
diagnosis made
A young woman presents with autoimmune
thrombocytopenia and is given the diagnosis of idiopathic
thrombocytopenic purpura but the malar rash and
concurrent arthritis are being missed
Premature closure
Failing to seek additional information
after reaching a diagnostic conclusion
A young woman with fever, leucocyturia and haematuria
assumed to have urinary tract infection but ignoring
significant proteinuria due to SLE nephritis
Narrowing of
differential diagnosis,
selection of diagnosis
and validation
Fever, arthritis and a heart murmur attributed to SLE and
not to endocarditis
A middle-aged woman with seizures and negative workup including ANA and anticardiolipin antibodies but
clinician missed the malar rash and the photosensitivity
Selection of a course of
action
Outcome
Clinical decision is judged based upon
the outcome rather than the reasoning
and the evidence supporting the
decision
SLE patient with pulmonary embolism and pericarditis
develops hemopericardium and tamponade as a result of
anticoagulation. The clinician believes it was a mistake to
anti-coagulate based upon this complication
Omission
Undue emphasis on avoiding adverse
effect of a therapy results in underutilization of beneficial treatment
Patient with severe proliferative glomerulonephritis is not
offered immunosuppressive therapy because of the fear of
infections
Data modified from Kassirer (2010)1.
1.
Kassirer, J.P. Teaching clinical reasoning: case-based and coached. Acad Med 85, 1118-24 (2010).