Clinical Decision Making Flashcards
Describe the effect of extraneous factors on clinical decision-making using an example.
Junior-senior relationship may lead to the wrong decision being made
What is Confirmatory Bias?
The tendency to search for or seek, interpret, and recall information in a way that confirms one’s preexisting beliefs or hypotheses, often leading to errors
What is the Sunk Cost Fallacy?
Rationally, the only factor affecting future action should be future cost/benefit ratio BUT humans do not always act rationally
Often, the more we have invested in the past, the more we are prepared to invest in a problem in the future
What is the Anchoring Effect?
It is a cognitive bias that describes the tendency to rely too heavily on the first piece of information offered when making decisions. Once the anchor is set, future decisions are made by adjusting away from that anchor
For example; A working diagnosis of acute pancreatitis may seem quite reasonable in a 60-yr-old man who has epigastric pain and nausea, who is sitting forward clutching his abdomen
However, the patient states that he has had no alcohol in many years and investigations show normal blood levels of pancreatic enzymes
Clinicians may simply dismiss or excuse conflicting data (eg, the patient is lying, his pancreas is burned out, the laboratory made a mistake)
What is Gambler’s Fallacy?
A logical fallacy involving the mistaken belief that past events will affect future events when dealing with independent events
Define conditional probability.
Measures the probability of an event happening given that another event has occurred
What is Bayes’ theorem and what is it used for?
It is a theorem that measures conditional probability
It is used in screening that involves false positives and false negatives such as mammograms/breast cancer
State some strategies for improving clinical decision-making.
1) Education and training:
Recognise that heuristics and biases may be affecting our judgement even though we may not be conscious of them
2) Feedback:
Increase number of autopsies
Conduct regular and systematic audits
Follow-up patients
3)Accountability:
Establish clear accountability and follow-up for decisions made
4) Generating alternatives:
Counteract the effect of top-down processing by generating alternative theories and looking for evidence to support them rather than just looking for evidence that confirms our preferred theory (confirmatory bias)
5) Consultation:
Understand and employ statistical principles e.g. Bayes’theorem
Use of algorithms and decision support systems
How do clinicians usually make decisions?
Intuitive understanding of probabilities is combined with cognitive processes called heuristics to guide clinical judgment.
Heuristics are often referred to as rules of thumb, educated guesses, or mental shortcuts.
Heuristics usually involve pattern recognition and rely on a subconscious integration of patient data with prior experience
What are Kahneman’s two systems for decision making?
Hot system:
Emotional, “GO”, simple, reflexive, fast
Cold system:
Cognitive, “KNOW”, complex, reflective, slow
What is representativeness heuristic?
Subjective probability that a stimulus belongs to a particular class based on how ‘typical’ of that class it appears to be (regardless of base rate probability)
e.g. A 60-yr-old woman who has no known medical problems and who now looks and feels well reports experiencing symptoms earlier of feeling short of breath, sweaty and clammy, feeling sick, and feeling faint.
This does not match the typical profile of an MI, which is typically characterised by chest pain.
BUT, it would be unwise to dismiss that possibility because MI is common among women of that age and has highly variable presentations.
How does age change how people respond to framing?
When presented with treatment descriptions described in positive, negative, or neutral terms, older adults are significantly more likely to agree to a treatment when it is positively described than they are to agree to the same treatment when it is described neutrally or negatively
What is meant by the availability heuristic?
Probabilities are estimated on the basis of how easily and/or vividly they can be called to mind.
People tend to heavily weigh their judgments toward more recent information
For example, a clinician who recently missed the diagnosis of pulmonary embolism in a healthy young woman who had vague chest discomfort but no other findings or apparent risk factors might then overestimate the risk in similar patients and become more likely to do chest CT angiography for similar patients despite the very small probability of disease.
