Reducing Diagnostic Error

Tim Shoen, MD

Campaign for Quality

October 17, 2014

Disclosure

No financial interest to disclose

Thanks to Mark Graber, MD, President, SIDM.

Sue Sheridan

Wall Street Journal

The Biggest Mistake Doctors Make

Misdiagnoses are Harmful and Costly

But they're often preventable

Laura Landro

November 17, 2013

Patient Safety Awareness 2014

Creating a world where patients and those that care for them are free from harm.

www.npsf.org

Society to Improve Diagnosis in Medicine

We envision a world where diagnosis is accurate, timely, and efficient.

www.improvediagnosis.org

Gregory House, MD

Objectives

• Review Incidence

• Contribution of Cognitive and System factors

• Improvement Efforts

Diagnosis

The satisfaction of solving The Riddle…is every doctor’s measure of his own abilities; it is the most important ingredient in his professional self-image.

Dr. Sherwin Nuland

How We Die 1994

Human Error

• Skill Based – error rate 1:1000

• Rule Based– error rate 1:100

• Knowledge Based– error rate 1:2

Preventable Harm

ErrorAdvers

e

Event

Diagnostic Error

• Delayed Diagnosis

• Missed Diagnosis

• Wrong Diagnosis

Expert A. Elstein: 10-15%

Patient Survey

One third relate a Dx error affected themselves, family

SecondReviews

Radiology and Pathology: 2-5% cancers missed

Look backs 30% of subarachnoid hemorrhage misdiagnosed; 39% of dissecting AAA delayed diagnosis; A third of neurological diagnoses wrong or likely wrong

Autopsy Major unexpected discrepancies that would have changed the management are found in 10-20%

Estimates of Dx Error Rate

Estimates Diagnostic Error Rate

Trauma 8% of pts have missed injuries

General ER .6% of 5000 admitted pts at Wayne State

MI 2-3% of pts sent home have an MI; 90% of pts admitted don’t have an MI or ACS

Liability 47% claims high severity cases alleged Dx related

OutpatientClinic

1:20 patients experience dx error each year

Diagnostic Errors

• Are common and cause enormous harm

• Estimates 40,000-80,000 annual deaths

• Overlooked with emphasis on system improvement

• Measurement tools lacking

Etiology of Diagnostic Error

Both System and Cognitive Errors

46%

Cognitive Error Only28%

System Error Only19%

No Fault Error Only7%

Cognitive Errors: 320

Faulty Synthesis 83 %

Faulty Knowledge

3 %

Faulty Data Gathering 14 %

Diagnostic Errors

• Are common and cause enormous harm

• Most errors involve both system and cognitive components.

• Cognitive errors most often reflect problems using intuition

Cognitive Psychology

Brain

Hard wiringAmbient conditions/ContextTask characteristicsAge and ExperienceAffective stateGenderPersonality

EducationTrainingCritical thinkingLogical competenceRationalityFeedbackIntellectual ability

Pattern Recognition

Repetition

Executiveoverride

Dysrationaliaoverride Calibration Diagnosis

PatientPresentation

PatternProcessor

RECOGNIZED

NOTRECOGNIZED

1

2

Dual Process Model of Clinical Reasoning

Heuristic and Bias

• Confirmation Bias

• Availability

• Anchoring

COGNITIVE ERRORS Most common:

• Premature closure (39)• Faulty context generation (26)• Faulty perception (25)• Failed heuristic (23)

Problems Solutions

• Faulty context• Premature closure• Failed heuristic• Framing errors

• Consider the opposite• Crystal ball experience• Reflection• Be comprehensive• Learn the antidotes

How can we make diagnosis more reliable ?

DX Reasoning

The PROBLEM: COMPLEXITY

The SOLUTION:NOT training; NOT redesign

A Checklist

The B-17, and its checklist, flew the next 1.8 million miles without an accident. The military obtained over 13,000, and the B-17 was the workhorse of the Allied air force in

World War II.

13,000 known diseases, syndromes, injuries

4,000 possible tests

6,000 medications, treatments, and surgeries

The average limits of human working memory:7 discrete items

Complexity in Medicine

The Surgical Checklist• WHO sponsored study in 8 countries• 19 item checklist:

– Sign in + Time out + sign out• Evaluated in 3733 operations:• Results:

– Major complications fell from 11 to 7%– Death rate fell from 1.5 to 0.7% (p = 0.003)

Haynes et al. NEJM 360: 491-9, 2009

A Checklist for Diagnosis

Obtain YOUR OWN history Perform a focused, purposeful exam Take a “Diagnostic Time Out”

Was I comprehensive ? Did I consider the inherent shortcomings of using my

intuition (heuristics) ? Was my judgment affected by bias ? Do I need to make the diagnosis now or can it wait ? What’s the worst case scenario?

Embark on the plan, but ENSURE FOLLOW-UP & FEEDBACK

Structured ReflectionV ascularI nfections & intoxicationsT rauma & toxinsA uto-immuneM etabolicI diopathic & iatrogenicN eoplasticC ongenitalC onversion (psychiatric)D egenerativeE ndocrine

Possible Solutions

• National Agenda

• Research

• Health IT

• Clinical Reasoning Education

Summary

• Diagnosis errors are common and harmful

• High quality healthcare requires high quality diagnosis

• Diagnostic errors are costly• Healthcare Organizations are well

positioned to lead efforts to reducing these errors

Case Studies

• Maine Medical Center– Physician Reporting

• SoCal Kaiser Permanente– Electronic Records to Trace Diagnostic

Error

Reference

Reference

Questions?

Tim Shoen, MD

shoen7754@aol.com

Subject: Dx Error