The previously cited estimate of annual deaths from medical errors in the US was a 1999 Institute of Medicine (IOM) report that has been considered limited and outdated. The report describes an incidence of 44,000-98,000 deaths annually.(4) However, Makary and Daniel recently gained widespread publicity with their estimate that medical error constitutes the 3rd leading cause of death in the US.(16) Although, the estimate may be an overestimate, it still has brought medical errors to the forefront of healthcare. Despite huge advances in imaging technology and lab testing as well as an explosion of Free Open Access Medical Education (FOAM), the misdiagnosis rate detected through autopsy studies has not changed significantly over the past century.
Studies on diagnostic error in emergency medicine have shown error rates between 1 and 12%, and it’s been suggested that cognitive error, or some flaw in the decision making process (as opposed to a lack of knowledge), is present in about 95% of these cases…
Cognitive errors likely underlie diagnostic errors that are made in the Emergency Department. Over time I have realized that our specialty is most vulnerable, because we commit errors (delayed diagnosis, missed diagnosis, unnecessary imaging) which may look like no-brainers to our colleagues in other specialties.
Great, let’s fix it then. If it were only so easy…
A story repeatedly cited about a jogger who came across a man on his knees under a streetlight one evening. He explained that he had dropped his wedding ring. The jogger offered to help him search, and he accepted. With no luck after half an hour, the jogger asked the man if he was sure he had dropped the ring at the place where they were searching. The man replied that he actually dropped it several yards away in the shadows. ‘‘Then why are we looking here?’’ asked the jogger. ‘‘Because the light is better,’’ came the reply.
Remember that elderly patient that presented with weakness and you did a cardiac work- up, but in reality had the “dwindles”… A cardiac cause may occur in the elderly, however, discussing the psychosocial issues are much more time intensive versus a cardiac evaluation and exclusion, which is mentally easier to grasp and evaluate then the latter…
Errors are universal but since we are often the front line to our respective institutions, the brunt falls on us. As a specialty we need to find a way to minimize errors by developing a conceptual framework and strategies in this critical aspect of patient safety. FOAM has us focus our attention in attempting to increase our clinical acumen but we need to value the importance of improving our communication with both patients and physicians…
Diagnostic errors arising through cognitive errors are those that are associated with failures in perception, failed heuristics, and biases are referred to as cognitive dispositions to respond (CDRs). There are a number of strategies for reducing them (‘‘cognitive debiasing’’) such as METACOGNITION, a reflective approach to problem solving that involves stepping back from the immediate problem to examine and reflect on the thinking process.(2) How do I accomplish this, when I just evaluated 8 patients in the last hour and two are requesting an update? Attempting to maintain balance in such a difficult setting is a challenge…
Some Unique operating characteristics of ED predisposing to medical error
- High Diagnostic Uncertainty
- High Decision Density
- High Cognitive Load
- High level of activity
- Interruptions and Distractions
- Sleep Deprivation
- Shift Work
- Shift Changes
- Emotional Perturbation
There is huge list of errors which we come across as clinicians and not surprisingly, all of them are evident in emergency medicine, a discipline that has been described as a ‘‘natural laboratory of error. (1)’’
Various biases leading to errors:
1 Anchoring Bias: Anchoring bias causes physicians to stay with their initial impression of a case and fail to adjust to new information that would make the initial impression less likely. This often leads to prematurely ending their search or premature closure
2 Availability: Recent experience with a disease may inflate the likelihood of its being diagnosed. Conversely, if a disease has not been seen for a long time (is less available), it may be under diagnosed.
3 Premature closure: a powerful bias accounting for a high proportion of missed diagnoses. It is the tendency to apply premature closure to the decision- making process, accepting a diagnosis before it has been fully verified (when the diagnosis is made, the thinking stops)
4 Ascertainment bias: occurs when a physician’s thinking is shaped by prior expectation; stereotyping and gender bias are both good examples.
5 Fundamental attribution error: the tendency to be judgmental and blame patients for their illnesses rather than examine the circumstances that might have been responsible. In particular, psychiatric patients, minorities, and other marginalized groups.
Cognitive De-biasing Strategies to Reduce Diagnostic Error
1 Develop insight/ awareness: Reflect on known cognitive biases, take a step back or excuse yourself from the room when you note that this is occurring. Evaluate your approach and determine what is best for a particular situation.
2 Consider alternatives: Establish forced consideration of alternative possibilities. Encourage routinely asking the question: What else might this be? For example, any patient who presents with flank pain/hematuria, force yourself to consider aortic dissection. Circle several options on differential diagnosis in the EHR and remove each circle that you feel, has been confidently excluded by your examination and history…
3 Metacognition: Train for a reflective approach to problem solving: Metacognition is the process of actively stepping back from the pushes and pulls of the immediate situation (de-anchoring), reminding oneself of the limitations and failings of memory, seeing the clinical problem in a wider perspective than that dictated by the obvious presentation, perhaps reminding oneself of specific lapses or failures in the past, and finally activating known cardinal rules or caveats. This is best accomplished with the patient. Review the presentation and discuss why or why not a certain condition appears to be less likely. Not only do patients now feel engaged in the process but it also demonstrates that you care and have listened to their complaint.
4 Decrease reliance on memory: Improve the accuracy of judgments through cognitive aids: phone apps, clinical practice guidelines or algorithms. You may have felt the presentation is benign but the calculated Heart score is 5, do you need to reconsider your disposition? PECARN suggest maybe a head CT may be indicated. Cognitive Unloading, expend less energy on memory retrieval tasks, you will have more available for critical thinking.
5 Make task easier: Provide more information about the specific problem to reduce task difficulty and ambiguity. Make available rapid access to concise, clear, well-organized information. Type a differential diagnosis on the EHR upon initial evaluation and re-visit the differential diagnosis when initial tests are back and when deciding disposition. Formalizing our Handover: ‘SBAR’ Mnemonic for Handover – Situation, Background, Assessment, Recommendation
6 Minimize time pressures: Provide adequate time for quality decision- making. Discharge and cognitive off load patients that are ready and provide that patient you are uncertain of, more time to review complaint and incorporate family members into the medical decision making process.
Feedback: Provide rapid and reliable feedback as possible to decision makers so that errors are immediately appreciated, understood, and corrected, resulting in better calibration of decision makers. Team communication is important not only in resuscitation, but in all ED patient encounters! Consider discussing with the nurse and the rest of your team what you think the most likely diagnosis is, what you’re worried about, what your management plan is and what you think the disposition might be, rather than only filling out orders for the nurses. This allows everyone to ‘be on the same page’ and may improve efficiency as well as decrease medical error.
7 Understanding “how we think”:
Type 1: The Intuitive/Reflexive Approach involves automatic decision making based on pattern recognition. It is fast, requires little effort and usually brings you the correct diagnosis, but it may be prone to error, especially in the setting of limited clinical experience. As diligent emergency clinicians this is the area we are most comfortable in and spend most of our time in…
Type 2: The Analytical/Problem-Solving Approach is more critical and logical. This is when you step back and think more carefully about the patient’s presentation. It involves estimating pretest probabilities, continuous self-questioning, and considering alternative diagnoses. While it takes more effort, more time and is more resource intensive, its use in certain clinical settings is essential to an accurate diagnosis.(17)
The current view of this decision making in EM model is that it’s not a matter of whether Type 2 is better than Type 1 but rather, how expert decision makers blend these two systems. Experts use their experience and past errors/mistakes to reflect on their knowledge and their biases and develop heuristics (cognitive short-cuts) and cognitive forcing strategies that allow them to use their Type 1 system for rapid decision making in EM rather than having to slow down using their Type 2 system.
It is humorous to consider our fallibility when we are so often expected to be perfect. Most descriptions of this topic focus on the content incorporated into this blog post: dual process theory, biases and possible solutions. However, several problems exist with dual process theory and its application to medicine that must be acknowledged…
Dual process theory is not only the theory of human cognition. The clean distinction thinking into system one and system two is questionable. There are certainly times we are on cruise control and other times that we are deliberate and analytical. However, the complete separation of the two processes may be incorrect. I certainly don’t know… but think it’s important to recognize that human cognition is likely a lot more complex.
Although I have read and listened to Keylimes blog on Zwan et al. study that concluded the lack of benefit in teaching Metacognition. (10) I find it hard to comprehend that teaching young physicians how to become better physicians would ever be a bad thing. Although, I will agree that there is no real evidence supporting the premise that a significant component of diagnostic error is due to cognitive biases. Yet, I do believe the above processes can only positively impact patient care. If you teach this process as an identification process and it does not shape your clinical practice, then the teaching is a failure not the process…
1 Learn and practice metacognition.
2 Develop your own strategies to reduce errors: discussion, (verbalize the case to a consultant or colleague) and/or development of mental checklists
3 Use a Problem Solving approach when in your career and allow it to mold your clinical practice, so it is used in the appropriate clinical setting
If these tools, rather than catching errors, result in our increasing testing in patients below a tests threshold, we will end up causing harm. I think we need to be aware of these biases, but not because we will be able to eliminate error from medicine, but as a reminder that we are all fallible.
We need to get away from the historical practice of blaming individuals for errors and this culture must be replaced by root-cause analysis that identifies process and systemic areas of weakness.
Hijinio Carreon DO, FACEP
3 Crosskerry, P. The Importance of Cognitive Errors in Diagnosis and Strategies to Minimize Them. Academic Med. August 2003, 1-6.
4 To Err is Human: Building A Safe Health Care System, Linda T. et al., The Committee on Quality of Health Care in America Institute of Medicine, National Academy Press, Washington, D.C. 1999.
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8 Parush A, et al. Situational Awareness and Patient Safety. The Royal College of Physicians and Surgeons of Canada. 2011.
9 Reuben Strayer. The Preferred Error. Emergency Medicine Updates. June 11th, 2014.
10 Zwaan L, Monteiro S, Sherbino J, Ilgen J, Howey B, Norman G. Is bias in the eye of the beholder? A vignette study to assess recognition of cognitive biases in clinical case workups. BMJ Quality and Safety. 2016 Jan;[ePub ahead of print]
11 BMJ 2016; 353 doi: http://dx.doi.org/10.1136/bmj.i2139 (Published 03 May 2016)
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17 Kahneman, Daniel. Thinking, fast and slow. Farrar Straus & Giroux, 2011. Print.
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