Common sense or cognitive bias and groupthink: does it belong in our clinical reasoning?

Abstract

You go to a medical equipment shop and buy a stethoscope and reflex hammer for £105. The stethoscope cost £100 more than the reflex hammer. How much did the reflex hammer cost? If your answer to the above question was £5, you may have been using common sense (type-1 reasoning). If on the other hand your answer was based on analytical thinking (type-2 reasoning) your answer would have been more like £2.50. Like most successful biological organisms, we have evolved for economy of effort, to save energy. Type-2 reasoning requires more effort and more time than type-1, so we tend to apply common sense …