© 2006 Wotkyns Creative Dennis J. Boyle, MD Denver Health/UCDSOM COPIC 2014 Cognitive Error in Medicine Thinking like Sherlock

2 Outline Scope of the problem How we diagnose Examples Improving the process

The diagnosis is every doctor's measure of his own abilities and is the most important ingredient of his self-image Nuland

The death of one man is a tragedy The death of millions is a statistic Stalin 4

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80,000 deaths a year Leape JAMA

So what is a diagnostic error? 7

What is a diagnostic error? A missed or delayed opportunity to make a timely diagnosis Singh JAMA IM

Diagnostic error is divided into cognitive and systems. Today we will look at cognitive… 9

Cognitive error is different 10

Cognitive error is complex…  Evolving/NYD 11

 Evolving/NYD  Pt issues 12 Complex…

 Evolving/NYD  Pt issues  System issues 13 Complex…

 Evolving/NYD  Pt issues  System issues 14 Complex…

 Evolving/NYD  Pt issues  System issues  WHO 12,420 diseases 15 Complex…

Error rate  80% of charts no diff DX  54% feel they make one error/month  Rad/Path rate 2%  IM rate 10 – 15%  1/1000 outpatient visits Singh 2013 Graber Am Jmed 2008 Arthur Elstein 16

Error results in……  #1 cause of lawsuits  Overtreatment  Emotional impact  Wasted money and time Gelhart NEJM 2009  17

Can we afford to be perfect- breast imaging 18

And cognitive errors occur because…. 19

But it’s still complicated…..A stroke alert story 20

But it’s still complicated…..A stroke alert story 21

22 How we think - System I vs. System II Kahneman and Tvertsky

23 How we think - System I vs. System II Kahneman and Tvertsky

24 How we think - System I vs. System II Kahneman and Tvertsky

25 Where does this all happen? Lehrer J How we decide. 2009

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Thin slicing - Separating wheat and chaff 27

Blink 28 Where is the lesion?

Blink 29

Blink 30 Where was the lesion?

System I - Blink 31

System II - Hypothetico-deductive style  Rigorous  List all possibilities  Probabilistic  Occurs in prefrontal cortex 32

System II- Hypothetico-deductive style Problem list  Lower GI symptoms  Arthralgias  High ESR  Low vitamin D  Low back pain  Osteoporosis J Hirsh 2011 Differential DX  Sprue  Reactive arthritis  Colitis w Spondy  Vasculitis-PAN  Fibromyalgia/ IBS w another cause of ESR 33

How much time do you spend in system I  20%  50%  75%  95% 35

How much time do you spend in system I  95% 36

The brain is a cognitive miser 37

Toggle function system I and II 38

Stress and fatigue push us to system I 39

The problem with System I is biases – name the bias 40

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42 Anchoring bias - rely on first impression Premature closure – decide too early

43 Last 2 patients had flu - Availability bias – what comes to mind

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Affection bias – taking care of loved ones Evolving - NYD 45

Framing bias – how it’s presented 46 I’ve got this pt I’d like you to see. She’s a psych patient with CP….. He’s a drunk with abdominal pain Mcneil NEJM 1982

Fast track patient with a cold 47

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Anchoring and framing biases 49

At sign out knee trauma F/U US 50

Framing and premature closure 51

Where is the lesion? 52 9

Search satisficing - Stop the diagnostic process once one diagnosis has been made- 53 9

December 2000

Ten Years Later

Alliteration bias – previous errors

57 Anchoring bias is the big kahuna……

Top 10 fixes for diagnostic errors 58

#10 Reflective listening and build a story 59

#10 75% of the DX comes from the HX 60

#9 Mindfulness - reflective practice 61

#8 Build your knowledge base 62

#8 And try to figure it out 63

#7 Always do a differential Problem list  Lower GI symptoms  Arthralgias  High ESR  Low vitamin D  Low back pain  Osteoporosis J Hirsh 2011 Differential DX  Sprue  Reactive arthritis  Colitis w Spondy  Vasculitis-PAN  Fibromyalgia/ IBS w another cause of ESR 64

#6 Use your Bayes A 63 YO w CP and DM ? treadmill 65

#5 Use Occams razor 66

#4 IT –the original tricorder…think Amazon... 67

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 18 hour w/o sleep = ETOH 0.05%  And when you’re behind, tired or overloaded…. Beer pic #3- Be aware of stress

#2 – Always ask what else could this be? 70

#1 Think like Sherlock  Sherlock clip Manede Psych res

So what do I do? If you’re sure What else could it be ? If You’re not - NYD 72

So what do I do? If you’re sure If You’re not - NYD S O A P Think like Sherlock! 73

Homework for all of us!!! If you’re sure What else could it be ? If You’re not - NYD S O A P Think like Sherlock! 74

75 The problem is not knowledge but thinking. Can improve your diagnosing? Dennis Boyle M.D. Please fill out the feedback form The rubber hits the road 1 ERS point