Berlin Questionnaire: Assess Your Sleep Apnea Risk

What Is the Berlin Questionnaire?

The Berlin Questionnaire is a validated screening tool that estimates your risk of having obstructive sleep apnea (OSA). It was developed in 1996 at a conference on sleep in primary care held in Berlin, Germany, and formally published by Netzer et al. in 1999 in the Annals of Internal Medicine. The goal was simple: give primary care physicians a quick, structured way to identify patients who should be referred for a sleep study.

It is not a diagnosis. No questionnaire can replace a polysomnogram or home sleep test. But as a first step, the Berlin Questionnaire has been used in clinics worldwide for over 25 years because it works. It identifies high-risk patients with enough reliability that doctors can prioritize who needs testing soonest.

The questionnaire is especially useful in primary care settings where sleep apnea is easy to miss. An estimated 80% of moderate to severe OSA cases remain undiagnosed (Young et al., 1997, Sleep). Most patients don't walk in complaining about apneas. They complain about fatigue, headaches, and high blood pressure. The Berlin Questionnaire connects those dots.

If you've been wondering whether your snoring, tiredness, or blood pressure issues could be related to sleep apnea, this tool gives you a structured way to find out. Take the Berlin Questionnaire now to see where you stand.

How the Berlin Questionnaire Works

The questionnaire consists of 10 questions organized into three categories. Each category is scored independently, and your overall risk depends on how many categories come back positive.

Category 1: Snoring and Witnessed Apneas (5 Questions)

This section asks about snoring frequency, snoring loudness, whether anyone has noticed you stop breathing during sleep, and how often these events occur. It captures the hallmark nighttime symptoms of obstructive sleep apnea.

Positive if: 2 or more items in this category score positive.

Most people underestimate their snoring. If you sleep alone, you may not know how loud or frequent it is. A bed partner's observations are often the most reliable data point here. For more on why snoring matters, see our guide on why snoring should not be ignored.

Category 2: Daytime Sleepiness (3 Questions)

This section asks about daytime fatigue, sleepiness while driving, and how often you feel tired or fatigued after sleeping. It measures the downstream impact of disrupted sleep.

Positive if: 2 or more items score positive.

Excessive daytime sleepiness is one of the most common consequences of untreated sleep apnea, but it is also one of the easiest to dismiss. People attribute it to stress, aging, busy schedules, or caffeine dependence. The Berlin Questionnaire forces you to quantify it rather than explain it away.

If sleepiness is your primary concern, the Epworth Sleepiness Scale provides a more detailed measurement of that specific dimension.

Category 3: BMI and Blood Pressure (2 Items)

This section captures two major physiological risk factors: body mass index (BMI) over 30 and a history of high blood pressure (hypertension).

Positive if: BMI is greater than 30 OR you have been told you have high blood pressure.

The connection between obesity and sleep apnea is well established. Excess tissue around the neck and upper airway increases the likelihood of collapse during sleep. Hypertension is both a cause and a consequence. Untreated OSA contributes to resistant hypertension, and the two conditions frequently co-occur. For a deeper look at risk factors, see sleep apnea risk factors.

Overall Risk Classification

• High risk: 2 or more categories are positive
• Low risk: 0 or 1 categories are positive

That's the entire scoring system. It is deliberately simple. The questionnaire is designed for primary care triage, not nuanced clinical assessment. Its job is to sort patients into "should be tested soon" and "can monitor for now."

How Accurate Is the Berlin Questionnaire?

The original validation study (Netzer et al., 1999) tested the Berlin Questionnaire against polysomnography (the gold standard for sleep apnea diagnosis) in a primary care population. The results:

• Sensitivity: approximately 86% for moderate to severe OSA (AHI >= 15)
• Specificity: approximately 77%
• Positive predictive value: approximately 89% in the studied population

In practical terms, that means the questionnaire correctly identifies about 86 out of 100 people who actually have significant sleep apnea. It also means roughly 23 out of 100 people without significant OSA will be incorrectly flagged as high risk (false positives).

The Berlin Questionnaire is better at catching true cases than it is at ruling them out. A high-risk result is a strong signal. A low-risk result is not an all-clear. If you have concerning symptoms (witnessed breathing pauses, gasping awake at night, crushing daytime fatigue), a low-risk Berlin score should not stop you from pursuing testing.

Subsequent studies in different populations have shown some variability. Sensitivity ranges from roughly 69% to 86% depending on the population studied, and specificity from about 56% to 77%. The questionnaire performs best in populations with a high prevalence of obesity and hypertension, which aligns with its design emphasis on Category 3.

Berlin vs. STOP-BANG vs. Epworth

Three screening tools come up most often in sleep apnea evaluation. Each serves a different purpose.

Feature	Berlin Questionnaire	STOP-BANG	Epworth Sleepiness Scale
Questions	10 across 3 categories	8 yes/no items	8 situation-based ratings
Focus	Symptom patterns over time	Binary risk factors	Daytime sleepiness only
Scoring	Category-based (2+ positive = high risk)	Count-based (5+ = high risk)	Sum (0-24, >10 = excessive sleepiness)
Sensitivity	~86% (moderate-severe OSA)	~90% (moderate-severe OSA)	Not designed to detect OSA directly
Best for	Primary care screening with frequency data	Quick preoperative or clinic screening	Quantifying subjective sleepiness
Developed	Netzer et al., 1999	Chung et al., 2008	Johns, 1991
Take it	Berlin Questionnaire	STOP-BANG Screener	Epworth Scale

The Berlin Questionnaire is unique among these tools because it accounts for symptom frequency. It does not just ask whether you snore. It asks how often, how loud, and whether it bothers other people. That frequency-based approach captures the chronic, progressive nature of obstructive sleep apnea more effectively than a binary yes/no checklist.

The STOP-BANG questionnaire (Chung et al., 2008, Anesthesiology) is the simplest of the three. Eight yes/no questions covering Snoring, Tiredness, Observed apneas, Pressure (blood pressure), BMI, Age, Neck circumference, and Gender. Its sensitivity for moderate to severe OSA is approximately 90%, making it slightly more sensitive than the Berlin. It is widely used in surgical and anesthesia settings because it takes under two minutes. Take the STOP-BANG.

The Epworth Sleepiness Scale (Johns, 1991, Sleep) measures something different entirely. It quantifies how likely you are to doze off in eight everyday situations. It does not screen for apnea directly. A high Epworth score tells you that you have excessive daytime sleepiness, which has many possible causes. A low Epworth score does not mean you are free of sleep apnea. Many people with significant OSA have adapted to their fatigue and score normally. Take the Epworth.

The best approach is to use more than one. If all three tools point in the same direction, you have a clearer picture. If results are mixed (for example, high Berlin but normal Epworth), that's still useful information to bring to your doctor.

What to Do After Taking the Berlin Questionnaire

If Your Result Is High Risk

A high-risk Berlin score means two or more of the three categories are positive. This is a meaningful signal. The next step is to talk to your doctor about a sleep study.

There are two main types of sleep study: an in-lab polysomnogram and a home sleep test. For most adults with suspected obstructive sleep apnea, a home sleep test is the standard first step. It is done in your own bed, takes one night, and results typically come back within a week. Our diagnosis process guide walks through the full pathway from screening to treatment.

If you want to prepare before your appointment, consider also taking the STOP-BANG and Epworth screeners. Walking in with results from all three gives your doctor a comprehensive picture and demonstrates that you have done your homework.

A home sleep test kit (opens in new tab) can also be ordered through some direct-to-consumer services, though insurance coverage is best when your doctor orders it. A fingertip pulse oximeter (opens in new tab) can give you preliminary overnight oxygen data to share at your appointment, though it cannot diagnose apnea on its own.

If Your Result Is Low Risk

A low-risk score means zero or one category was positive. This is reassuring but not definitive. Remember the specificity limitations: the Berlin Questionnaire misses roughly 14% of true cases.

If you have specific symptoms that concern you (loud snoring, witnessed breathing pauses, waking up gasping, persistent morning headaches), a low-risk Berlin score does not mean you should ignore them. Bring those symptoms to your doctor regardless. Our guide on sleep apnea symptoms can help you identify what to watch for.

Some people with sleep apnea are not overweight and do not have hypertension. Their Category 3 stays negative, which makes it harder for the Berlin to flag them. The STOP-BANG questionnaire captures some of these cases better because it includes age, neck circumference, and gender as independent risk factors.

If You Are Already Diagnosed and on CPAP

If you have already been diagnosed with sleep apnea and are using a CPAP machine (opens in new tab), screening tools are behind you. Your focus is now on optimizing therapy.

Import your CPAP data into CPAP Clarity to track your AHI, leak rates, pressure patterns, and usage over time. The analyzer reads your SD card data directly in your browser (nothing is uploaded to a server) and gives you a clear picture of how your therapy is performing night by night.

When to See a Doctor

Regardless of your Berlin Questionnaire score, certain symptoms warrant a conversation with your doctor sooner rather than later:

• Witnessed breathing pauses during sleep. If someone has watched you stop breathing, that is the single strongest indicator for sleep apnea. Do not wait.
• Gasping or choking that wakes you up. Your body is intervening to restart breathing. This is not normal.
• Morning headaches that resolve within an hour or two of waking. These are consistent with overnight oxygen desaturation.
• Excessive daytime sleepiness that affects safety. If you struggle to stay awake while driving, operating machinery, or performing safety-critical work, this is urgent.
• Resistant hypertension. If your blood pressure remains elevated despite medication, untreated sleep apnea is one of the most common underlying causes.

Sleep apnea is treatable. The gap between suspecting you have it and getting diagnosed is usually smaller than people expect. Our step-by-step guide on how to get tested for sleep apnea covers exactly what to expect.

Take the Berlin Questionnaire

Ready to find out where you stand? The Berlin Questionnaire on CPAP Clarity takes about three minutes to complete. Your answers are scored instantly in your browser. Nothing is stored, nothing is sent anywhere.

If you want the most complete picture, take all three screeners:

1. Berlin Questionnaire for overall OSA risk
2. STOP-BANG Screener for a quick binary risk check
3. Epworth Sleepiness Scale for daytime sleepiness severity

Then bring the results to your next doctor's appointment, or use them to start the conversation about a sleep study. The hardest part is not the screening. It's deciding to take it seriously.

As an Amazon Associate, CPAP Clarity earns from qualifying purchases. All recommendations are based on published research and clinical guidelines. This content is for educational purposes and does not constitute medical advice. Consult your physician for diagnosis and treatment decisions.