According to the General Medical Council’s Guidance on Good Practice:
You must tell patients if an investigation or treatment might result in a serious adverse outcome, even if the likelihood is very small.
Sounds like good advice. Seems to ensure the patient makes the best decision. But does it?
Our brains aren’t designed to handle tiny probabilities. When we focus on them, our mind overestimates their significance. For example, if I told you there’s a .0001% chance you’ll die from a certain treatment, statistically you should ignore that piece of information. But you won’t. Death, after all is scary, and anything above a 0% chance of occurrence is impossible to ignore completely. This focusing illusion might steer you towards a bad decision.
So, should doctors withhold all information about extremely rare outcomes? Perhaps, but it’s a difficult question to answer, with both legal and ethical considerations.
In organizations though, where decisions aren’t normally matters of life and death, the question isn’t as difficult. The devil’s advocate, who is usually expected (and encouraged) to voice every risk imaginable, should be a bit more disciplined. She should avoid presenting a catastrophe scenario so unlikely, that the benefits of consideration are outweighed by the focusing illusion it will inevitably create for others.
Now, if you’re the devil’s advocate, reading this might make you nervous. You might think, “But what if it turns out to be the one time the rare event actually does occur?”
Take a deep breath. That’s the focusing illusion talking. It’s insidious.