The STOP-Bang questionnaire: a quick sleep apnea quiz, explained

The STOP-Bang questionnaire is a short sleep apnea quiz that doctors use to decide who should be tested. It has eight yes or no questions, takes about a minute, and gives a score from 0 to 8. A higher score means a higher chance of obstructive sleep apnea. It's a screening tool, though, not a test, and only a sleep study can tell you whether you have sleep apnea.

What is the STOP-Bang questionnaire?

STOP-Bang is a screening questionnaire for obstructive sleep apnea, built from eight features linked to the condition. Researchers in Toronto first published a four-question version, STOP, in 2008 for patients about to have surgery. In that study, adding body mass index, age, neck size and sex raised its ability to catch sleep apnea, and the eight-item version became STOP-Bang.

The name is a memory aid. STOP stands for snoring, tiredness, observed breathing pauses and blood pressure. Bang stands for BMI, age, neck circumference and gender. The questionnaire belongs to University Health Network in Toronto, which runs the official STOP-Bang site.

The original study gave the STOP questions to 2,467 surgical patients, and 211 of them had an overnight sleep study to check the results. Since then it has been tested in sleep clinic patients, surgical patients and other groups, including commercial bus drivers.

What are the STOP-Bang questions?

The eight STOP-Bang questions cover four symptoms and four risk factors, and each yes is worth one point. The table below paraphrases each item from the official STOP-Bang site so you can check yourself. Count your yes answers as you go.

Some of these you can't change, such as age and sex. They are on the list because they raise the odds of sleep apnea, not because they cause it on their own. If you need help with the "observed" question, ask a bed partner, or read our guide to sleep apnea warning signs together.

What does your STOP-Bang score mean?

Your STOP-Bang score is the number of yes answers, from 0 to 8, and a higher score means a higher risk of obstructive sleep apnea. The official STOP-Bang site sorts scores into three groups for the general population:

• Yes to 0 to 2 questions is low risk
• Yes to 3 or 4 questions is intermediate risk
• Yes to 5 to 8 questions is high risk

A middle score can also count as high risk. The site says that yes to two or more of the four STOP questions plus being male, having a BMI over 35, or having a neck of 16 inches (40 cm) or more puts you in the high-risk group.

A 2016 review in Chest by the questionnaire's developers explains why the score matters. As the score rises from 0 to 2 up to 7 or 8, the chance of moderate to severe sleep apnea rises from 18% to 60%, and the chance of severe sleep apnea rises from 4% to 38%.

How accurate is STOP-Bang?

STOP-Bang is accurate at catching sleep apnea, which is what a screening tool is for. A 2015 meta-analysis in PLOS One pooled 17 studies with 9,206 patients. In sleep clinic patients, it correctly flagged 90% of people with any sleep apnea, 94% of those with moderate to severe sleep apnea and 96% of those with severe sleep apnea.

The trade-off is a high number of false alarms. In the same meta-analysis, specificity in sleep clinics was 49% for any sleep apnea, 34% for moderate to severe and 25% for severe. In plain terms, many people who score 3 or more turn out not to have that level of sleep apnea when tested.

Higher scores are more telling. In sleep clinic patients, the chance of severe sleep apnea was about 25% at a score of 3, and rose step by step to 35%, 45%, 55% and 75% at scores of 4, 5, 6 and 7 or 8. Results in surgical patients followed a similar pattern at slightly lower levels.

The 2016 Chest review adds one more useful number. For a score of 3 or more, the negative predictive value was 90% for moderate to severe sleep apnea and 100% for severe. So a low score fairly reliably points away from the more serious forms, though it can still miss milder cases.

Why do surgeons and anesthetists use it?

STOP-Bang started in operating departments because undiagnosed sleep apnea matters during surgery. The 2008 study that introduced it described obstructive sleep apnea as a major risk factor for problems around the time of an operation, and noted that no screening tool had yet been validated in surgical patients. The goal was a quick set of questions that could be asked at a pre-surgery clinic.

That's why you may meet STOP-Bang on a pre-operative form even if you've never thought about your sleep. If you're asked these questions before an operation, answer as accurately as you can. The answers help the team decide whether sleep apnea needs more attention, so ask the clinic what your score means for your care and whether you should be tested.

Can you take the STOP-Bang test online?

Yes, the official STOP-Bang site has a free version of the questionnaire with a built-in BMI calculator, so you don't need to work out your BMI by hand. You need your height, weight, age and collar size, plus honest answers about snoring and tiredness.

It helps to measure your neck rather than guess. Wrap a tape measure around your neck at the level of the Adam's apple. If you don't have one, the collar size of a shirt that fits comfortably is a fair stand-in, which is how the official site phrases the question.

What are the limits of a sleep apnea quiz?

The main limit is that a quiz can't diagnose sleep apnea. The American Academy of Sleep Medicine's 2017 guideline makes a strong recommendation that clinical tools, questionnaires and prediction algorithms not be used to diagnose sleep apnea in adults without a sleep study or home sleep apnea test.

There are other limits worth knowing:

• STOP-Bang was built and tested mostly in surgical and sleep clinic patients. People in those groups are more likely to have sleep apnea than the general public, which affects how a score should be read.
• The sex and age items mean a man over 50 starts with two points before any symptom is counted. A woman with real symptoms can score lower, which is one reason symptoms matter more than the number. Our guide to sleep apnea in women covers signs that get missed.
• Answers rely on what you know. Many people have no idea they stop breathing at night, so the "observed" question depends on someone else noticing. Sleep apnea can also happen without loud snoring.

Screening everyone isn't recommended either. In 2022, the US Preventive Services Task Force concluded that evidence was insufficient to weigh the benefits and harms of screening adults who have no symptoms. Questionnaires like STOP-Bang are most useful when someone already has signs worth looking into.

What should you do after taking the quiz?

If you scored 3 or more, or you have symptoms whatever your score, talk to a doctor about testing. The NHS advises seeing a GP if your breathing stops and starts in your sleep, you make gasping, snorting or choking noises, or you always feel very tired during the day. It suggests bringing anyone who has seen your symptoms to the appointment.

Testing is usually simpler than people expect. The NHS says you may wear sensors overnight that check your breathing and heartbeat, and you can usually do this at home. The result is an apnea-hypopnea index, or AHI. An AHI of 5 to 14 is mild, 15 to 30 moderate and over 30 severe. Our guides to home sleep apnea tests, what happens at a sleep study and what AHI means walk through each step.

Bring your STOP-Bang answers with you. Writing down your snoring, tiredness and anything a partner has seen gives your doctor a quick picture. Our list of questions to ask your doctor about snoring can help you prepare.

If you scored low and feel fine, there's nothing to act on. If anything changes, such as new loud snoring or unusual daytime sleepiness, take the quiz again and see a doctor if your answers shift.

This article is general information, not medical advice. A questionnaire can't replace an assessment by a doctor.

Read next

• What is a home sleep apnea test, and what should you expect?
• 10 warning signs of sleep apnea you shouldn't ignore
• Snoring vs. sleep apnea: how to tell the difference

* This content is for informational and educational purposes only and is not medical advice. It is not intended to diagnose, treat, cure or prevent any disease or health condition. Talk to a qualified healthcare provider about your health.