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?





• Test utilization and interpretation poorly taught

Why the errors?






• Insufficient preceptor time

Why the errors?







• Diagnostic opportunities random and insufficient

Why the errors?







• 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

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


Portal


Portal✓New Text




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


Portal✓New Text



Updated video online lecture

series




Portal✓New Text




Mobile app



Mobile App

• Leverage technology created by AgileMD

– Link to Transient Loss of Consciousness

• Other options under consideration

https://www.agilemd.com/flowcharts/reader/modules/535041aa1c17d16c1b000015/files/fi_f78744f56802e69

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


Problem Statement:Transient Loss Of Consciousness ℹ


Task:History☑ Abrupt onset☑ Short duration☑ Spontaneous Recovery

User selection will change• Problem statement• Differential Dx• And next task






Task:History☑ Abrupt onset☑ Short duration☑ Spontaneous Recovery

Problem Statement:Syncope


Task:History Dehydration VV symptoms ℹ Cardiac Symptoms ℹ


Portal✓New Text




Mobile app

Educational Curricula



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




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

The Wrong Diagnosis: A Modern Paradox & Calamity

Documents

Transcript of The Wrong Diagnosis: A Modern Paradox & Calamity