Pat Croskerry

The importance of cognitive errors in diagnosis and strategies to minimize them.

In the area of patient safety, recent attention has focused on diagnostic error. The reduction of diagnostic error is an important goal because of its associated morbidity and potential preventability. A critical subset of diagnostic errors arises through cognitive errors, especially those associated with failures in perception, failed heuristics, and biases; collectively, these have been referred to as cognitive dispositions to respond (CDRs). Historically, models of decision-making have given insufficient attention to the contribution of such biases, and there has been a prevailing pessimism against improving cognitive performance through debiasing techniques. Recent work has catalogued the major cognitive biases in medicine; the author lists these and describes a number of strategies for reducing them (“cognitive debiasing”). Principle among them is metacognition, a reflective approach to problem solving that involves stepping back from the immediate problem to examine and reflect on the thinking process. Further research effort should be directed at a full and complete description and analysis of CDRs in the context of medicine and the development of techniques for avoiding their associated adverse outcomes. Considerable potential exists for reducing cognitive diagnostic errors with this approach. The author provides an extensive list of CDRs and a list of strategies to reduce diagnostic errors.

Achieving quality in clinical decision making: cognitive strategies and detection of bias.

Clinical decision making is a cornerstone of high-quality care in emergency medicine. The density of decision making is unusually high in this unique milieu, and a combination of strategies has necessarily evolved to manage the load. In addition to the traditional hypothetico-deductive method, emergency physicians use several other approaches, principal among which are heuristics. These cognitive short-cutting strategies are especially adaptive under the time and resource limitations that prevail in many emergency departments (EDs), but occasionally they fail. When they do, we refer to them as cognitive errors. They are costly but highly preventable. It is important that emergency physicians be aware of the nature and extent of these heuristics and biases, or cognitive dispositions to respond (CDRs). Thirty are catalogued in this article, together with descriptions of their properties as well as the impact they have on clinical decision making in the ED. Strategies are delineated in each case, to minimize their occurrence. Detection and recognition of these cognitive phenomena are a first step in achieving cognitive de-biasing to improve clinical decision making in the ED.

Clinical Cognition and Diagnostic Error: Applications of a Dual Process Model of Reasoning.

Both systemic and individual factors contribute to missed or delayed diagnoses. Among the multiple factors that impact clinical performance of the individual, the caliber of cognition is perhaps the most relevant and deserves our attention and understanding. In the last few decades, cognitive psychologists have gained substantial insights into the processes that underlie cognition, and a new, universal model of reasoning and decision making has emerged, Dual Process Theory. The theory has immediate application to medical decision making and provides an overall schema for understanding the variety of theoretical approaches that have been taken in the past. The model has important practical applications for decision making across the multiple domains of healthcare, and may be used as a template for teaching decision theory, as well as a platform for future research. Importantly, specific operating characteristics of the model explain how diagnostic failure occurs.

Cognitive debiasing 1: origins of bias and theory of debiasing

Numerous studies have shown that diagnostic failure depends upon a variety of factors. Psychological factors are fundamental in influencing the cognitive performance of the decision maker. In this first of two papers, we discuss the basics of reasoning and the Dual Process Theory (DPT) of decision making. The general properties of the DPT model, as it applies to diagnostic reasoning, are reviewed. A variety of cognitive and affective biases are known to compromise the decision-making process. They mostly appear to originate in the fast intuitive processes of Type 1 that dominate (or drive) decision making. Type 1 processes work well most of the time but they may open the door for biases. Removing or at least mitigating these biases would appear to be an important goal. We will also review the origins of biases. The consensus is that there are two major sources: innate, hard-wired biases that developed in our evolutionary past, and acquired biases established in the course of development and within our working environments. Both are associated with abbreviated decision making in the form of heuristics. Other work suggests that ambient and contextual factors may create high risk situations that dispose decision makers to particular biases. Fatigue, sleep deprivation and cognitive overload appear to be important determinants. The theoretical basis of several approaches towards debiasing is then discussed. All share a common feature that involves a deliberate decoupling from Type 1 intuitive processing and moving to Type 2 analytical processing so that eventually unexamined intuitive judgments can be submitted to verification. This decoupling step appears to be the critical feature of cognitive and affective debiasing.

From Mindless to Mindful Practice — Cognitive Bias and Clinical Decision Making

Much diagnostic error is caused by cognitive bias. More than 100 biases affecting clinical decision making have been described, and many medical disciplines acknowledge their pervasive influence on our thinking. Training in critical thinking may ameliorate the problem.

Emergency medicine: A practice prone to error?

The last decade has witnessed a rapidly growing public and academic interest in medical error, an interest that has culminated in the emergence of the science of error prevention in health care. The impact of this new science will be felt in all areas of medicine but perhaps especially in emergency medicine (EM). The emergency departments unique operating characteristics make it a natural laboratory for the study of error. These characteristics, combined with the complex and myriad activities of EM, predict vulnerability to a multitude of errors. Overcrowding and other resource limitations impair continuous quality improvement, and many errors result from high decision density, excessive cognitive load and flawed thinking in the decision-making process. A large proportion of these errors have serious outcomes but an even higher proportion are preventable. The historical practice of blaming individuals for errors needs to be replaced by root-cause analysis that identifies process and systemic weaknesses. Quantitative and qualitative methods are needed to detect, describe and classify error at all levels in the system. Research is needed into the processes that underlie EM error. Educational initiatives should be developed at all levels, for everyone from undergraduate trainees to practicing emergency physicians. Changes in societal attitudes will be an important component of the new culture of patient safety. A nationwide reporting system is proposed to disseminate error information expediently. Canadian EM providers are in a pivotal position to provide leadership to the Canadian health care system in this important area.

Cognitive debiasing 2: impediments to and strategies for change

In a companion paper, we proposed that cognitive debiasing is a skill essential in developing sound clinical reasoning to mitigate the incidence of diagnostic failure. We reviewed the origins of cognitive biases and some proposed mechanisms for how debiasing processes might work. In this paper, we first outline a general schema of how cognitive change occurs and the constraints that may apply. We review a variety of individual factors, many of them biases themselves, which may be impediments to change. We then examine the major strategies that have been developed in the social sciences and in medicine to achieve cognitive and affective debiasing, including the important concept of forcing functions. The abundance and rich variety of approaches that exist in the literature and in individual clinical domains illustrate the difficulties inherent in achieving cognitive change, and also the need for such interventions. Ongoing cognitive debiasing is arguably the most important feature of the critical thinker and the well-calibrated mind. We outline three groups of suggested interventions going forward: educational strategies, workplace strategies and forcing functions. We stress the importance of ambient and contextual influences on the quality of individual decision making and the need to address factors known to impair calibration of the decision maker. We also emphasise the importance of introducing these concepts and corollary development of training in critical thinking in the undergraduate level in medical education.

The theory and practice of clinical decision-making

HERE is a story about a philosopher and a psychologist having a drink. The philosopher asks: why did the chicken really cross the road? The psychologist replied: well, as the chicken lacks any formal reasoning or decisionmaking capabilities, it seems unlikely that its action was spurred by any conscious motivation, so I’d say it was instinct. The exchange brings out some salient points for the present discussion on clinical decision-making in anesthesiology. Firstly, we generally assume that all human behaviour with the exception of reflexes is driven by some motivating influence. Motives in turn lead to decision-making which characterizes human behaviour. The first decision of the day, getting out of bed, arises from a complex of motivators which may include: vocation, making a living, hunger, a sense of duty, threat, guilt and others. Once that first decision is made, the rest of the day consists of a series of decisions and actions, one after the other, some in parallel, of lesser or greater complexity. If the environment is predictable and routine, some decisions and actions can be relegated to an almost automatic level, such as driving. In contrast, when there is uncertainty a sustained level of vigilance and attention may be required. At the highest level of cognitive function we can make a decision to monitor our decision-making this is metacognition. Good problem solving, sound judgement, and effec

Better clinical decision making and reducing diagnostic error.

A major amount of our time working in clinical practice involves thinking and decision making. Perhaps it is because decision making is such a commonplace activity that it is assumed we can all make effective decisions. However, this is not the case and the example of diagnostic error supports this assertion. Until quite recently there has been a general nihilism about the ability to change the way that we think, but it is now becoming accepted that if we can think about, and understand, our thinking processes we can improve our decision making, including diagnosis. In this paper we review the dual process model of decision making and highlight ways in which decision making can be improved through the application of this model to our day-to-day practice and by the adoption of de-biasing strategies and critical thinking.

Emotional Influences in Patient Safety

Objective: The way that health care providers feel, both within themselves and toward their patients, may influence their clinical performance and impact patient safety, yet this aspect of provider behavior has received relatively little attention. How providers feel, their emotional or affective state, may exert a significant, unintended influence on their patients, and may compromise safety. Methods: We examined a broad literature across multiple disciplines to review the interrelationships between emotion, decision making, and behavior, and to assess their potential impact on patient safety. Findings: There is abundant evidence that the emotional state of the health care provider may be influenced by factors including characteristics of the patient, ambient conditions in the health care setting, diurnal, circadian, infradian, and seasonal variables, as well as endogenous disorders of the individual provider. These influences may lead to affective biases in decision making, resulting in errors and adverse events. Clinical reasoning and judgment may be particularly susceptible to emotional influence, especially those processes that rely on intuitive judgments. Conclusions: There are many ways that the emotional state of the health care provider can influence patient care. To reduce emotional errors, the level of awareness of these factors should be raised. Emotional skills training should be incorporated into the education of health care professionals. Specifically, clinical teaching should promote more openness and discussion about the providers feelings toward patients. Strategies should be developed to help providers identify and de-bias themselves against emotional influences that may impact care, particularly in the emotionally evocative patient. Psychiatric conditions within the provider, which may compromise patient safety, need to be promptly detected, diagnosed, and managed.