Question Quality (Point Biserial)

The Question Quality Distribution chart gives you a quick snapshot of how well your test questions are working. Think of it as a report card for your test – it shows you which questions are doing a good job of telling the difference between students who understand the material and those who need more help.

How It Works

Each question on your test gets a score that measures how well it separates strong students from struggling students. Good questions should be answered correctly more often by students who did well overall on the test, and answered incorrectly more often by students who struggled with the test as a whole.

What Each Color Range Means

Red Zone (≤ 0.09) – “Problem Questions”

What it means: These questions aren’t working properly. Both strong and weak students are getting them wrong at about the same rate.

What to do:

• Review these questions carefully – they may be confusing or have unclear wording
• Consider removing them from your grade calculations
• Rewrite or replace these questions before using the test again

Common issues: Trick questions, multiple correct answers, or content that wasn’t taught clearly

Orange Zone (0.1 – 0.19) – “Needs Work”

What it means: These questions are doing a poor job of identifying who understands the material.

What to do:

• Look at how you worded these questions
• Check if the content matches what you actually taught
• Consider revising before the next test

Yellow Zone (0.2 – 0.29) – “Okay for Now”

What it means: These questions are working adequately but could be better.

What to do:

• These are acceptable to keep using
• Try to improve them when you have time
• Look for ways to make the wording clearer

Light Green Zone (0.3 – 0.39) – “Good Questions”

What it means: These questions are doing a good job of measuring student understanding.

What to do:

• Keep using these questions
• These can serve as models for writing new questions
• Minor tweaks might make them even better

Dark Green Zone (≥ 0.4) – “Excellent Questions”

What it means: These are your best questions – they clearly separate students who know the material from those who don’t.

What to do:

• Definitely keep these questions
• Use them as examples when creating new tests
• These questions are reliable indicators of student learning

What Your Overall Distribution Should Look Like

Ideal situation: Most of your questions fall in the yellow, light green, and dark green zones. This means your test is doing a good job of measuring what students have learned.

Warning signs: If you have many questions in the red and orange zones, your test may not be giving you accurate information about student understanding.

Goal to aim for: Try to have at least 80% of your questions in the yellow zone or better (0.2 and above).

How to Improve Your Questions

When you find questions that aren’t performing well, here are practical ways to review and adjust them:

Standards and Alignment

Check if your question matches what you taught:

• Does the question test the specific learning objective from your lesson?
• Is the cognitive level appropriate (remembering facts vs. applying concepts)?
• Does it align with your state standards?

Red flag example: Testing multiplication when you taught addition, or asking students to analyze when you only taught them to recall facts.

Bias and Sensitivity

Make sure all students have a fair chance:

• Avoid references that only some students would understand (specific sports, cultural events, or expensive activities)
• Use names and examples that represent diverse backgrounds
• Check that the question doesn’t advantage students from specific social or economic groups

Red flag example: A math word problem about skiing lessons when many students have never seen snow.

Language and Vocabulary

Keep the language clear and appropriate:

• Use vocabulary at your students’ reading level
• Avoid unnecessarily complex sentence structures
• Define any technical terms that aren’t being tested
• Watch out for double negatives or confusing phrasing

Red flag example: Using “subsequently” when you could say “next,” or testing math skills with overly complex reading passages.

Structure and Context

Organize your question clearly:

• Put the most important information first
• Keep word problems concise and relevant
• Make sure the context supports, rather than distracts from, the learning objective
• Use familiar scenarios when possible

Red flag example: A science question buried in an irrelevant story about characters your students don’t know.

Answer Choices (for multiple choice)

Create effective options:

• Make sure there’s only one clearly correct answer
• Write wrong answers (distractors) that seem reasonable to students who partially understand
• Avoid “all of the above” or “none of the above” unless absolutely necessary
• Keep answer lengths similar

Red flag example: One answer choice that’s obviously much longer or shorter than the others, or joke answers that no student would seriously consider.

Visuals

Use images and graphics effectively:

• Ensure visuals are clear and easy to see
• Make sure images support the question rather than just decorate it
• Check that visual elements are accessible to all students
• Avoid cluttered or distracting graphics

Red flag example: A blurry graph, decorative images that don’t relate to the question, or charts with text too small to read.

Practical Review Process

For questions scoring in the red or orange zones:

1. Read the question aloud – Does it sound confusing or unclear?
2. Check your answer key – Is there truly only one correct answer?
3. Think about your students – What might have confused them?
4. Review the six areas above – Which ones might be causing problems?
5. Revise and test – Make changes and see if the question performs better next time

For questions scoring in yellow:

• Look for one or two quick improvements from the areas above
• These questions are usable but can be enhanced

For questions scoring in green zones:

• Keep using these questions
• Use them as models when writing new questions
• Share successful strategies with other teachers

Quick Action Steps

1. Start with your lowest-scoring questions – Focus your revision time where it will have the biggest impact
2. Pick one improvement area – Don’t try to fix everything at once
3. Test with a small group – Ask a colleague or a few students to review revised questions
4. Keep successful questions – Build a bank of your best-performing questions for future use
5. Track improvements – Notice which revision strategies work best for your students

Remember: Every teacher writes questions that don’t work perfectly the first time. This data helps you become better at creating tests that accurately measure what your students have learned, leading to more effective teaching and fairer grading.

**Note This article intended to be viewed in conjunction with Question Analysis