Research shows that the two best ways to screen candidates are a general knowledge/IQ test (which is mostly illegal in the US) and a work sample test. The fact

Research shows that the two best ways to screen candidates are a general knowledge/IQ test (which is mostly illegal in the US) and a work sample test. The fact that a work sample test predicts work success makes a lot of sense - have them do the thing you want to pay them to do and evaluate how well they do it. Duh! You should screen folks using the work that they are going to be doing for you. Are you hiring someone to code on a whiteboard? No? Then why are they doing that in the interview?