Designing a Test Developing a Table of Specifications Jennifer Fager Director of Curriculum and Assessment
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It's time for your midterm. What should be tested? What topics were discussed and for how long? What type of items will you use? How long will students have to take the test? How many items/points should be used given the amount of time available? To respond to these questions, test writers have used a Table of Specifications.
Developing a Table of Specifications Example a Unit Test on Item Type and Grading Systems Topics Taught linked Time Spent on to essential student Topic learning outcomes for the course
% of Total Time Spent on Topic (Time Spent on Topic divided by Total Time)
Writing multiplechoice items Writing true-false items Writing matching items Writing short-answer questions Writing essay questions Grading systems TOTALS
1 class session
25%
Number of Items/Points per Topic Area (% of Total Time Spent times Total Number of Items/Points) 25
.5 class session
12.5%
13
.5 class session
12.5%
13
.25 class session
6.25%
6
.25 class session
6.25%
6
1.5 class sessions 4 class sessions
37.5% 100%
37 100 points
Steps: 1. Determine which topics will be included on the assessment. Typically, these include lectures, discussions, readings, etc. or any other assigned learning. 2. Estimate approximately how much time was spent on each topic. 3. Add up the time spent per topic. 4. Calculate the percentage of time spent per topic by dividing the time spent on each topic by the total amount of time. For example, on Grading Systems I spent 1.5 class sessions thus 1.5/4.0=37.5%.
5. Determine how many questions or points should be included on the exam. Estimate how much time students are likely to spend on each item to be certain that students will have an opportunity to answer all questions. This exam was worth 100 points as one class session = 3 hours. As a rule of thumb, for a 50-minute class period an instructor should not have more than about 50 multiple-choice items as it takes students about 1 minute per question. 6. Calculate the number of items per topic based on the time spent on topic. Using the example above, 1.5 class sessions were spent on Grading Systems which equaled 37.5% of the total time spent. To determine how many items/points should be on Grading Systems, multiply 37.5% times 100 points which equals 37.5 items rounded to 38. 7. Write or modify existing items based on the number of items per topic. This will not only guide the instructor, it will also guide students as topics that require more time on instruction are typically more complex and/or more important.
