I recently completed reading Daniel Kahneman's book "Thinking Fast and Slow". It is a tour de force. Perhaps my only criticism is that despite being well written in a very readable style, it is still very dense because it is so filled with important observations and insights. I had to read and re-read most sections. My copy of the book is dog-eared and marked with mini-Post-it notes.
Toward the end to the book Kahneman highlights a common perceptual error which I think is extraordinarily important and touches upon almost every element of human life and decision making. In short, our ability to understand the impact of low frequency events is fundamentally flawed. I sort of appreciated this prior to reading the book but Kahneman highlighted aspects of this I had not previously taken into consideration. The low frequency events can be either events we can benefit from or be hurt by.
This has huge implications within the realm of medical decision making. In the realm of dealing with well patients where we push interventions to avoid possible bad outcomes in the future, both physicians and patients vastly over estimate their likelihood of benefiting from screening or preventative therapeutic interventions. Simultaneously, we tend to vastly over estimate the likelihood from harm from measures vastly more likely to help us.
The issue is how we perceive possibility of events at the extremes. We are easily convinced to buy lottery tickets despite the fact that no one in their right mind and an understanding of the odds should buy a ticket for anything other than the entertainment value. Similarly, both our recommendations to patients and patient assessments of what they are likely to benefit from or be harmed by are riddled with the same biases. No where in our training are these issues consistently addressed. I find it hard to imagine we can even begin to address shared decision making and real informed consent without recognizing that decision making by patients and providers is driven by these biases.