The Item Analysis Report
This report brings together several different data elements associated with classroom test results. For each question, the percentage of students selecting each response, the correct answer as given on the key for the test, the difficulty of the question given as a percentage and the item effect or discrimination are listed. The report below is produced from the system that processes optical scanning answer sheets. The item analysis report for some computer-based testing systems have this information with additional displays that provide additional tools for evaluating questions. Can you spot the best and worst question in this brief report? You can refresh your memory of question difficulty here and question discrimination or question effect here.
A note about class size
If the class size is small (less than fifty) the item analysis has to be interpreted with some caution. The item effect (discrimination) is an estimate that is believable and interpretable only when the class size is larger than fifty. Even for small classes, big problems with specific questions can still be identified with some confidence. One thing that happens with small classes is that the values for both difficulty and discrimination will vary from class to class.