Heuristics Flashcards
What are heuristics?
mental shortcuts or rules of thumb used to simplify decision making and problem solving
Often sacrifices accuracy for efficiency and speed
Who described heuristics?
Tversky ad Kahneman in 1970s
What is representativeness?
Misinterpreting the likelihood of an event considering both the key similarities to its parent population and the individual characteristics that define that event
e.g. consider Steve, whom an acquaintance has described as ‘very shy and withdrawn, invariably helpful, but with little interest in people, or in the world of reality. A meek and tidy soul, he has a need for order and structure, and a passion for detail.’ After reading a description of Steve, do you think it’s more likely that Steve is a librarian, or a farmer? Intuitively, most of us feel like Steve must be a librarian because he’s more representative of our image of a librarian than he is our image of a farmer.
Explain availability
More recent and readily available answers and solutions are preferentially favoured because of ease of recall and incorrectly perceived importance
e.g. recent missed PE prompts excessive CTPA scanning in low risk patients
Explain anchoring and adjustment
Tendency to lock onto salient features in the patients initial presentation too early in the diagnostic process and failing to adjust this initial impression in light of later information
Explain the framing effec t
Reacting to a particular choice differently depending on how the information is presented to you
e.g. A pharmaceutical company may present new drug A as having a 95% cure rate, and suggest this is superior to drug B that has a significant 2.5% failure rate.
Explain base rate neglect
Occurs in medicine when the underlying incident rates of conditions or population-based knowledge are ignored as if they do not apply to the patient in question
Explain confirmation bias
Diagnosticians tend to interpret the information gained during a consultation to fit their preconceived diagnosis, rather than the converse.
Explain the conjunction rule
The incorrect belief that the probability of multiple events being true is greater than a single event. This relates to ‘Occam’s razor’ - a simple and unifying explanation is statistically more likely than multiple unrelated explanations.
Explain diagnostic momentum
Continuing a clinical course of action instigated by previous clinicians without considering the information available and changing the plan if required (particularly if plan commenced by more senior clinician).
