This document discusses how to calculate the difficulty index and discrimination index of test items to evaluate their quality. The difficulty index is the ratio of students who answered correctly to the total students. It ranges from 0 to 1, with values below 0.25 or above 0.75 indicating an item needs revision. The discrimination index measures how well items distinguish between top and bottom scoring groups, ranging from -1 to 1. Values below -0.5 mean the item should be discarded. The document provides examples of calculating both indexes and determining the appropriate action for each item based on the index values.