The Wrong Diagnosis: A Modern Paradox & Calamity
Transcript of The Wrong Diagnosis: A Modern Paradox & Calamity
The Wrong Diagnosis: A Modern Paradox & Calamity(Aligning cognitive and electronic technologies)
Scott Stern, M.D.
Professor of Medicine
Pritzker School of Medicine
University of Chicago
• Elementary school teacher celebrating her
67th birthday
• Came into emergency room feeling dizzy
& vomiting
• Diagnosed 3 times by 2 doctors as
gastroenteritis
• After multiple visits and several days, a
CT scan cerebellar stroke
• Hours later, Jane fell into a coma and
died
Meet Jane…
Part 1: THE PROBLEM
The Scary Truth
Clinicians often make the wrong diagnosis
Diagnostic Errors are Common
Recent 2015 IOM Report Improving Diagnosis in Health Care
– “..Diagnostic errors are a significant contributor to patient harm and have received too little attention until now."
– Estimates suggest 12 million people in the US will be affected by diagnostic error each year
– “Sometimes with devastating consequences.”
– Estimated cost…100-500B$/y
Imagine…
• What if …A pedagogical program could
↓ diagnostic error 30%?
• For every 3 patients seen, 1 less incorrect diagnosis
Why the errors?
• It’s difficult
First, its just not that easy!
– Vertigo
– BPPV
– Labrynthitis
– Meniere's disease
– Trauma
– Cerebrovascular disease
– Vertebrobasilar insufficiency
– Cerebellar or brainstem stroke
– Cerebellar hemorrhage*
– Migraine
– Cerebellar degeneration
– Alcohol intoxication
– Dilantin toxicity
– Cerebellar or brainstem tumors
– Near Syncope (see syncope section)
– Disequilibrium
– Multiple sensory deficits
– Parkinson's disease
– Normal pressure hydrocephalus
– Peripheral neuropathy
– Dorsal column disease
– B12 deficiency
– Syphilis
– Compressive lesions
– Cerebellar lesions
– Cerebellar tumor
– Cerebellar degeneration
– Cerebellar infarction
– Drugs (alcohol, benzodiazpeine,
anticonvulsants, aminoglycosides,
antihypertensives, muscle relaxants,
cisplatin)
– Nonspecific dizziness
– Psychiatric
– Depression
– Anxiety
– Somatization disorder
– Recently corrected vision
– Medication side effect
Differential diagnoses of dizziness
Why the errors?
• Reason #1: It’s difficult
• Reason #2: Educational approach & system are flawed!
• Focus on diseases not symptoms
• Faculty model system 1 thinking
System 1 thinking: Uses pattern recognition
• Advantages
– Fast
– Presents little cognitive load (easy)
• Disadvantages
– Fails when diseases have not been previously encountered…
– Fails to recognize atypical presentations
– Prone to error (biased by recent experiences)
– Requires years of experience
Model system 1 thinking not system 2
• System 2 thinking: Uses mental constructs to consciously
solve problem
– Presents larger cognitive load
– Exceptionally helpful when system 1 fails
– Rarely taught
• Optimal approach teach both system 1 and system 2
Model system 1 thinking not system 2
Why the errors?
• Reason #1: It’s difficult
• Reason #2: Educational approach & system are flawed!
• Focus on diseases not symptoms
• Faculty model system 1 thinking
• Test utilization and interpretation poorly taught
Why the errors?
• Reason #1: It’s difficult
• Reason #2: Educational approach & system are flawed!
• Focus on diseases not symptoms
• Faculty model system 1 thinking
• Test utilization and interpretation poorly taught
• Insufficient preceptor time
Why the errors?
• Reason #1: It’s difficult
• Reason #2: Educational approach & system are flawed!
• Focus on diseases not symptoms
• Faculty model system 1 thinking
• Test utilization and interpretation poorly taught
• Insufficient preceptor time
• Diagnostic opportunities random and insufficient
Why the errors?
• Reason #1: It’s difficult
• Reason #2: Educational approach & system are flawed!
• Focus on diseases not symptoms
• Faculty model system 1 thinking
• Test utilization and interpretation poorly taught
• Insufficient preceptor time
• Diagnostic opportunities random and insufficient
• Reason #3: Evaluation system flawed
• Emphasis on multiple choice question knowledge assessment
• Feedback is inconsistent
• Advancement is not competency based
The Outcome
The Research
2002 – present:
Development of Symptom to Diagnosis
• Focused on evaluating symptoms rather than disease
• Systematic literature review
• > 300 diseases that cause 31 common symptoms
• Collected sensitivity & specificity for history, physical exam, labs & x-rays
• Analyzed reviews & guidelines
• Developed data based diagnostic approaches & algorithms
• Published in Symptom to Diagnosis (2005, 2010, 2015, 2019)
(McGraw-Hill)
Four Key Observations
Observation #1
For each Problem/Symptom
• Key pivotal questions exists
• Organizes differential diagnosis into clinically distinct useful subsets
• Systematically narrow and focus the differential diagnosis and
testing
Stern S, et al. Symptom to Diagnosis 2010. McGraw Hill©
Observation #2
The focused differential could be explored… searching the remaining
diseases for…
• Risk factors
• Associated symptoms
• Signs
A New Paradigm
1. Describe Symptom
Pattern Recognition:
Rule out “Must-Not-Miss” Hypotheses
Test &
InterpretTreat
Diagnosis
confirmed
THE OLD Paradigm“Hunt & Peck”*
• Disease A
• Disease B
• Disease C
• Disease D
• Disease E
• Disease F
• Disease G
• Disease H
• Disease I
Diagnosis not confirmed
*Joe Rencic
Phase 1Data Acquisition
(History, physical exam, labs)
Pattern recognition Early hypothesis generationConsider “Must Not Miss” Hypotheses
Test
TreatPhase 3
Limit DifferentialUtilizing pivotal concepts
Differential group 1 Differential group 3Differential group 2
Explore limited differential• Risk factors• Associated symptoms• Signs
Rank & Test
Phase 2
TreatDiagnosis confirmed
Diagnosis not confirmed
TreatDiagnosis confirmed
THE NEW ParadigmApply a System
Hunt& Peck
Hunt&
PECK
Example
Transient Loss of Consciousness
Large differential diagnosis• Aortic stenosis
• AV heart block
• Carotid sinus syndrome
• Head trauma
• Hypertrophic cardiomyopathy
• Hypoglycemia
• Intoxication
• Orthostatic syncope
• Pulmonary embolism
• Seizure
• Sick sinus syndrome
• Subarachnoid hemorrhage
• Vasovagal syncope
• Ventricular tachycardia
• Wolf Parkinson White
Use pivotal points tofocus the differential diagnosis!
1 Distinguish syncope from non-syncope
In patients with syncopeDistinguish 3 types of syncope
2
Transient Loss of Consciousness
Syncope
Cardiac
AV blockHCM
Pulmonary EmbolismSSSVT
WPW
Reflex
VasovagalSituational
Orthostatic
DehydrationHemorrhageMedicationAutonomic
Non-Syncope
HypoglycemiaIntoxication
SeizureSubarachnoid hemorrhage
Trauma
Transient Loss of Consciousness
Syncope
Cardiac
AV blockHCM
Pulmonary EmbolismSSSVT
WPW
Reflex
VasovagalSituational
Orthostatic
DehydrationHemorrhageMedicationAutonomic
Non-Syncope
HypoglycemiaIntoxication
SeizureSubarachnoid hemorrhage
Trauma
Observation #3
• The history & physical exam are remarkably insensitive
• Medical curricula describe classic presentations which… are rarely seen
• Students memorize classic presentations
• Patients don’t read that book and don’t present that way!
• Students and residents exclude hypothesis from consideration
– premature closure and clinical reasoning errors
Sensitivity of 337 Classical
Signs & Symptoms in 101 Diseases
0%
5%
10%
15%
20%
25%
30%
35%
0-20% 21-40% 41-60% 61-80% 81-90% 91-100%
% o
f Fi
nd
ings
wit
h
Sen
siti
viti
es
in t
hat
Ran
ge
Sensitivity
}20%80%
Examples
Clinical Findings in
Pulmonary Embolism
Symptom/Sign Sensitivity (%) Negative LR
Dyspnea 59 - 85 0.3
Dyspnea, sudden onset 73 - 78 0.3
Pleuritic chest pain 32 - 74 0.8
Tachycardia 24 - 70 1.0
Pleural rub 3 - 18 1.0
Leg swelling 17 - 41 0.9
None of the expected findings are sensitive
Appendicitis: Fever
• Fever is not sensitive for appendicitis.
– Sensitivity 15-67%, negative LR = 1
Observation #4
Physical exam abnormalities often highly specific
• 43% of physical exam abnormalities > 90% specific
• Certain findings highly specific & worth looking for
Finding Sensitivity Specificity + LR
Jugular venous distention 17 - 50 98 17
S3 gallop 24 – 96 99 60
Evidence-Based Medicine
Clinical Findings in Heart Failure
Take home message for trainees
• The absence of signs virtually never rules out a
diagnosis
• The presence of signs helps to rule in disease
• Pay attention to what you find, not what is
missing
Do these education approaches work?
Evidence of Efficacy
• Recent multi-center study randomized medical students at
8 U.S. Medical Schools to Symptom to Diagnosis training
or not
• Studied evaluated impact on diagnostic accuracy using
computer based avatars and Symptom-To-Diagnosis
lectures
Results
A Vision for the Future
University of Chicago/Marcus Foundation
Program in Diagnostic Reasoning
• Platform under development that will …
– Developing Global Educational Technologies
– Utilize & optimize lessons learned from last 17y of research
– Be globally available for medical students, nurse practitioners,
other health care providers & medical schools
– Be Free
University of Chicago Symptom to Diagnosis
Portal✓New Text
Adaptive Learning Exercises
Podcasts(30 Planned)
Updated lectureseries
Mobile app
Educational Curricula
University of Chicago/Marcus Foundation
Portal
University of Chicago Symptom to Diagnosis
Portal✓New Text
Adaptive Learning Exercises
University of Chicago/Marcus Foundation
Program in Diagnostic Reasoning
Limitations of current simulations
• Learner is provided the relevant history and physical
exam
• Useful for pattern recognition
• Fails to train providers to obtain relevant information
Adaptive Exercises Overview
15 Symptoms, 3-5 cases each
• Abdominal Pain
• Acid base disorders
• Acute kidney injury
• Chest pain
• Cough & Pneumonia
• Delirium & Dementia
• Diagnostic Approach
• Dizziness
• Dyspnea
• Edema
• Headache
• Hyponatremia
• Hypotension & Shock
• Liver abnormalities & Jaundice
• Syncope
Preview
University of Chicago Symptom to Diagnosis
Portal✓New Text
Adaptive Learning Exercises
Podcasts(30 Planned)
Updated video online lecture
series
University of Chicago/Marcus Foundation
Program in Diagnostic Reasoning
University of Chicago Symptom to Diagnosis
Portal✓New Text
Adaptive Learning Exercises
Podcasts(30 Planned)
Updated lectureseries
Mobile app
University of Chicago/Marcus Foundation
Program in Diagnostic Reasoning
Mobile App
• Leverage technology created by AgileMD
– Link to Transient Loss of Consciousness
• Other options under consideration
Problem Statement:Transient Loss Of Consciousness ℹ
Differential Dx:• Aortic stenosis• AV Block• Dehydration ℹ• Hemorrhage• Seizure
Task:History Abrupt onset Short duration Spontaneous Recovery
Evolving Problem Statement(Changes as each selection is made)
Popup allow breadcrumbs to be shown(how the Problem statement changed)
Dynamic Differential Diagnosis(Items will gray out as problem statement changes)
User Tasks(with check boxes)
User Makes Selection
Get more information on the diagnosis of a particular disease
Problem Statement:Transient Loss Of Consciousness
Differential Dx:• Aortic stenosis• AV Block• Dehydration• Hemorrhage• Seizure
Task:History Abrupt onset Short duration Spontaneous Recovery
Problem Statement:Transient Loss Of Consciousness ℹ
Differential Dx:• Aortic stenosis• AV Block• Dehydration• Hemorrhage• Seizure
Task:History☑ Abrupt onset☑ Short duration☑ Spontaneous Recovery
User selection will change• Problem statement• Differential Dx• And next task
Problem Statement:Transient Loss Of Consciousness
Differential Dx:• Aortic stenosis• AV Block• Dehydration• Hemorrhage• Seizure
Task:History Abrupt onset Short duration Spontaneous Recovery
Problem Statement:Transient Loss Of Consciousness
Differential Dx:• Aortic stenosis• AV Block• Dehydration• Hemorrhage• Seizure
Task:History☑ Abrupt onset☑ Short duration☑ Spontaneous Recovery
Problem Statement:Syncope
Differential Dx:• Aortic stenosis• AV Block• Dehydration• Hemorrhage• Seizure
Task:History Dehydration VV symptoms ℹ Cardiac Symptoms ℹ
University of Chicago Symptom to Diagnosis
Portal✓New Text
Adaptive Learning Exercises
Podcasts(30 Planned)
Updated lectureseries
Mobile app
Educational Curricula
University of Chicago/Marcus Foundation
Program in Diagnostic Reasoning
U. of C. Diagnostic Reasoning Curriculum
– Clinical Pathophysiology & Therapeutics (CPPT)
oSymptom lectures Cases at conclusion of each
organ system
– Foundations in Clinical Medicine
oTransition course between pre-clinical sciences & wards
o7 full classroom days
Each half day focuses on 1 symptoms
Utilizes lectures, cases
FICMMonday Tuesday Wednesday Thursday Friday Monday Tuesday
AM -Course Into
-Diagnostic approach
-Hypotension lecture
-Electro-cardiogram review
-Chest X ray review
-Syncope lecture
-Syncope cases
-Abdominal pain lecture
-Abdominal pain cases
-Headache lecture
-Headache cases
-Chest pain lecture
-Chest pain cases
How to present on the wards
PM -Hypotension cases
-Edema lecture
-Edema cases
-Chest X ray cases
-Intro to lab medicine
-Owning your patients
-Acute Kidney Injury lecture
-Acute Kidney Injury cases
-Hyponatremia lecture
-Hyponatremia cases
-Hypoxia & Tachypnea lecture
-Hypoxia & Tachypnea cases
-Delirium lecture
-Delirium cases
ACLS (Advanced cardiac life support)
U. of C. Diagnostic Reasoning Curriculum
• Medicine clerkship
– Lectures on line
– Encouraged to read textbook (Symptom to Diagnosis)
– Symptom based case discussion/games
– OSCEs (Observed standardized clinical encounters)
– Urgent care electives
Urgent Care Elective
Monday Tuesday Wednesday Thursday Friday
AM Urgent care Urgent care Urgent care Urgent care Urgent care
PM Case reviewLiterature & diagnostic approach review
Case reviewLiterature & diagnostic approach review
Case reviewLiterature & diagnostic approach review
Case reviewLiterature & diagnostic approach review
Case reviewLiterature & diagnostic approach review
QuizzesQuizzes
Portal Navigation
Mobile App
IHPCases
Symptom Videos
Quizzes
Learning Exercises
Textbook
Podcast
Partners
• Collaborative group of U.S. educators interested in diagnostic error
• Current international partners
– KMC, Manipal, India
– Wuhan University, Wuhan China
• Hope to Develop Partners in other Regions
– Exploring new partnerships in Hong Kong
• Explore utilization in other groups
– Medical residents
– Other providers of primary care
oAdvance practice nurses
oPhysicians assistants
Summary
1. Diagnostic error is a tremendous problem
2. New educational paradigms/technologies can ↓ diagnostic error
3. Potential to improve patient care on a major global scale
4. Plan will develop regional recognized Centers of Excellence
5. A non-for-profit center provides maximum freedom to widely
disseminate products & maximize impact not limited by profit
concerns
Discussion/Questions