Item analysis allows the teacher to see how students performed overall on different questions. If students did particularly well or bad on a question, the teacher could re-examine the question to make sure that there is not a flaw in the question or answer options before making further plans for reteaching or review of a concept. A real life example of this is when I gave a test that, based on how I had worded the question, could be answered by two different options, whereas I had only considered one of the answers correct. I was able to give students who chose the correct "wrong" answer credit for their response and discovered that overall my students did significantly better than previously thought. It also allowed me to quickly identify a question that needed revision before the next administration.
