Sleep apnea test: how to get tested, what to expect and how to read your results

A sleep apnea test is an overnight recording of your breathing and blood oxygen while you sleep. It is done either at home with a small portable kit (a home sleep apnea test, or HSAT) or in a sleep lab with a full sleep study called polysomnography (PSG). Either way, a clinician has to order and interpret it. An online quiz or a smartwatch alert can tell you to get tested, but it cannot diagnose sleep apnea [1].

Testing is simpler than many people expect, and many adults can do it in their own bed. Here's each step, how home and lab tests compare, and how to read your results.

How do you get tested for sleep apnea?

Most people follow the same five steps:

1. Screen yourself. A short questionnaire shows whether your risk is low or high. It's a starting point, not an answer.
2. See a clinician. Your doctor or a sleep specialist reviews your symptoms and history. Medicare requires this in-person evaluation before the test for later CPAP coverage [10].
3. Take the test. Your clinician orders a home sleep apnea test or an in-lab polysomnogram [1][2].
4. Get your results. A sleep physician scores the recording and talks it through with you [3][6].
5. Start treatment if needed. You and your clinician choose a plan [2][6].

Not sure your symptoms are worth checking? Start with our guide to sleep apnea symptoms.

Can an online sleep apnea test diagnose you?

No. The American Academy of Sleep Medicine (AASM) gives a strong recommendation that questionnaires, clinical tools and prediction algorithms should not be used to diagnose obstructive sleep apnea (OSA) in adults without an actual sleep test [1]. These tools are for screening, which means sorting people by risk.

Screeners still help you decide whether to book an appointment. Try ours free:

• STOP-Bang: eight yes/no questions on snoring, tiredness, observed pauses, blood pressure, BMI, age, neck size and sex. In the populations studied, a score of 3 or more caught 93% of people with moderate-to-severe OSA [9]. It's built to flag risk, so it also flags many people who don't have OSA.
• NoSAS score: a point-based screener using neck size, obesity, snoring, age and sex.
• Berlin Questionnaire: groups snoring, tiredness and blood pressure questions into risk categories.
• Epworth Sleepiness Scale: measures daytime sleepiness, one of the signs doctors weigh. It doesn't test for apnea itself.

A high score is a reason to get tested. A low score doesn't rule sleep apnea out if you still have symptoms.

Home sleep apnea test vs in-lab sleep study: which is better?

Neither is better for everyone. A home test is built to confirm likely obstructive sleep apnea. An in-lab study measures much more, including your actual sleep [1][3][4].

Who should not use a home test?

The AASM recommends in-lab polysomnography rather than a home test for adults with any of these [1]:

• Significant heart or lung disease (heart failure and COPD are given as examples)
• Possible breathing-muscle weakness from a neuromuscular condition
• Low breathing while awake, or suspected low breathing during sleep (hypoventilation)
• Long-term opioid medication use
• A history of stroke
• Severe insomnia

It's also a poor fit if your risk is low, another sleep disorder is suspected, or setting up the kit would be physically hard [6].

Why a negative home test isn't always the final word

A home test is less sensitive than a lab study. It can't tell when you're awake, so time lying awake still counts, which can push your number down. It also misses events that cause a brief brain arousal without much oxygen drop [1].

A Cleveland Clinic sleep specialist says at-home tests "underestimate how severe your obstructive sleep apnea is." Roughly 7–8% also fail for technical reasons, like a sensor slipping off [4].

So the AASM is clear: if a single home test is negative, inconclusive or technically inadequate, the next step is an in-lab polysomnogram, not a second home test [1].

What is a home sleep apnea test like?

A home sleep apnea test is usually a single night [1][4]. Your clinic either hands you the kit or ships it to your door with instructions and a help line [4][6].

A typical kit has a small nasal tube for airflow, a fingertip oxygen sensor and stretchy chest and belly belts, all wired to a small recorder [4]. The AASM also accepts finger-based devices that measure blood-vessel tone (peripheral arterial tonometry) with oximetry and a movement sensor [1].

Here's how the night usually goes:

• Before bed: Follow your normal routine. Skip naps that day and avoid alcohol and caffeine after lunch [6].
• At bedtime: Attach the sensors as shown. You may be asked to press a button or keep a short sleep log [6].
• Overnight: Sleep as normally as you can. For the test to count, the AASM standard is at least 4 hours of usable oxygen and airflow data [1].
• In the morning: Remove the sensors. Depending on the device, you return it to the clinic, mail it back, or throw it away if it's disposable [6].

What happens during an in-lab sleep study (polysomnography)?

An in-lab study feels like a night in a plain hotel room. You change into sleepwear, a technologist attaches sensors, then checks them by asking you to move your eyes, mouth and legs [3].

The sensors are painless. Scalp, eye and chin sensors track your sleep stages, while belts, a nasal sensor and a finger clip track breathing and oxygen (see the table above) [3].

Do you need to sleep all night? No. Most people sleep worse than usual in a lab, and that rarely spoils the results. A night generally counts if you sleep two hours or more [3].

What is a split-night study?

The first part of the night is for diagnosis. If sleep apnea shows up clearly, you're fitted with a positive airway pressure (PAP) mask for the rest of the night [2]. When appropriate, the AASM suggests this over a full diagnostic night [1].

How to prepare for a sleep study

Cleveland Clinic recommends avoiding caffeine and alcohol for at least 8 hours beforehand and skipping naps. Shower, but skip lotions and hair products, which stop scalp sensors sticking. Remove nail polish or fake nails, which can interfere with the finger sensor. Keep taking your usual medicines unless told otherwise [3].

Can an Apple Watch or smartwatch test for sleep apnea?

Not in the diagnostic sense. Some watches can now flag possible sleep apnea, but these are notifications, not tests.

Apple Watch. In September 2024, the FDA cleared Apple's Sleep Apnea Notification Feature. It looks for "patterns of breathing disturbances suggestive of moderate-to-severe sleep apnea" over 30-day windows, in adults 18+ without a diagnosis. It "is not intended to diagnose, treat, or aid in the management of sleep apnea" [7].

In Apple's validation study, the feature flagged 66.3% of people with moderate-to-severe sleep apnea and stayed silent for 98.5% of people with normal-to-mild results [7]. So false alarms are rare, but it misses about a third of moderate-to-severe cases. As the FDA labeling says, "The absence of a notification is not intended to indicate the absence of sleep apnea" [7].

Samsung Galaxy Watch. In February 2024, Samsung announced FDA De Novo authorization for a feature that looks for signs of moderate-to-severe OSA. It is for adults 22 and older without a diagnosis, and it is not meant to help clinicians diagnose [8].

If your watch alerts you, treat it like a high screener score and book an appointment. Apple's alert includes a PDF of past data to share with your clinician [13]. If it never alerts you but you have symptoms, still get checked.

How to read sleep apnea test results

Your report centers on one number: breathing events per hour.

AHI (apnea-hypopnea index)

The AHI is the average number of apneas (full pauses) and hypopneas (partial drops in breathing) per hour of sleep [5]. Adult severity is usually grouped like this [5]:

Scoring rules matter. The AASM's recommended rule counts a hypopnea when reduced airflow comes with a 3% oxygen drop or a brief arousal; an alternative rule requires a 4% drop. The same night can give quite different AHIs under each rule [1]. For more, see what AHI means.

REI (respiratory event index)

On a home test, you may see REI instead of AHI. REI uses total recording time rather than sleep time, because the device can't tell when you're asleep [1]. That's one reason home results can run lower.

RDI (respiratory disturbance index)

The RDI adds a third event type to the AHI: respiratory effort-related arousals (RERAs). These are subtle breathing struggles that wake your brain briefly without a full apnea or hypopnea [1]. Your RDI is therefore equal to or higher than your AHI.

ODI and oxygen levels

The oxygen desaturation index (ODI) counts how often per hour your blood oxygen drops by a set amount. Reports may also show your lowest oxygen level. Our guide to SpO₂, ODI and T90 explains these.

Obstructive vs central events

Events are either obstructive (the airway collapses while you keep trying to breathe) or central (the brain briefly stops signaling you to breathe). This changes treatment, and a home test can't diagnose central sleep apnea [5].

Your sleep physician reads these numbers alongside your symptoms and health. A number alone isn't a diagnosis.

How much does a sleep apnea test cost?

Prices vary too widely to quote one figure. Cost depends on:

• Type of test. A home test uses fewer resources than a staffed lab night. But the AASM notes the savings shrink because failed or inconclusive home tests often lead to a second study [1].
• Your insurance. Most plans want a clinician's order, and many require prior authorization.
• Medicare. Part B covers Type I–IV sleep tests if you have signs and symptoms of sleep apnea and a provider orders it. Type I (full in-lab) tests are covered only in a sleep lab. After the Part B deductible, you generally pay 20% of the approved amount [11].
• Where you go. Hospital labs, independent sleep centers and telehealth services all price differently.

Ask your clinic and insurer about out-of-pocket cost first. For later CPAP coverage, Medicare requires an AHI or RDI of 15 or more (at least 30 events), or 5–14 (at least 10 events) plus a documented condition such as excessive sleepiness or high blood pressure [10].

What happens after a positive sleep apnea test?

You'll meet your clinician to choose a treatment [2][6]. Positive airway pressure (PAP) is the most studied and most often recommended therapy. Other options include oral appliances, weight loss and, in selected cases, surgery [2]. Our guide to sleep apnea treatment compares them.

If you start CPAP, the first months matter. Medicare covers an initial 12-week trial, then needs an in-person follow-up showing the therapy is helping [12]. See CPAP usage hours and adherence.

This is where tracking your own data helps. Your CPAP machine records nightly AHI, hours of use, leak and pressure. Apnealytics reads that data from the SD card of supported ResMed machines and turns it into clear nightly and long-term charts. It doesn't diagnose or change your therapy, but it makes trends easier to spot and discuss with your care team. Next reads: what a good AHI on CPAP looks like and our overview of sleep apnea machines.

If your test was negative but you still snore loudly, stop breathing at night or feel exhausted, go back to your clinician. The AASM suggests a second in-lab study can be considered when suspicion stays high [1]. Untreated sleep apnea carries real health risks, covered in is sleep apnea dangerous?

Frequently asked questions

How long does a sleep apnea test take?

A home sleep apnea test is usually one night in your own bed, and the AASM looks for at least 4 hours of usable data [1]. An in-lab study is also usually one night, and a night generally counts if you sleep two hours or more [3]. Scoring and results can take a few days to a few weeks, depending on the clinic [3][6].

Are home sleep apnea tests accurate?

They are accurate enough to confirm obstructive sleep apnea in the right people: adults with a high likelihood of moderate-to-severe OSA and no major other conditions [1]. But they are less sensitive than a lab study and can underestimate severity [1][4]. If a home test is negative or unclear and you still have symptoms, the AASM recommends an in-lab study next [1].

Can I test myself for sleep apnea without a doctor?

You can screen yourself with tools like STOP-Bang or a smartwatch notification, but you can't diagnose yourself. The AASM advises against diagnosing OSA from questionnaires or prediction tools alone [1]. A clinician needs to order and interpret a proper sleep test, and insurers generally require that before covering treatment.

Is a sleep apnea test covered by insurance?

Usually, if a clinician orders it for symptoms of sleep apnea. Medicare Part B covers Type I through IV sleep tests when you have signs and symptoms, with Type I covered only in a sleep lab [11]. You typically pay 20% after the deductible [11]. Private plans vary and often need prior authorization, so check with your insurer first.

Can a sleep apnea test be wrong?

Yes, especially a home test. It can miss mild cases or underestimate severity, since it counts time awake as if you were asleep [1][4]. Around 7–8% of home tests fail for technical reasons [4]. That's why a negative or inconclusive home test should be followed by an in-lab study if symptoms persist [1].

What does a sleep apnea test measure?

A home test measures breathing, breathing effort, blood oxygen and pulse [4][6]. An in-lab polysomnogram adds brain waves, eye movements, muscle activity, heart rhythm and video, so it can stage your sleep and detect other sleep disorders [3]. Both report an events-per-hour number, such as AHI or REI [1].

Can an Apple Watch diagnose sleep apnea?

No. Apple's FDA-cleared feature looks for breathing patterns "suggestive of moderate-to-severe sleep apnea" and sends a notification, but it is "not intended to diagnose" [7]. In testing, it caught about two-thirds of moderate-to-severe cases [7]. An alert means see a clinician. No alert doesn't mean you're in the clear.

Sources

1. Kapur VK et al. Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline. J Clin Sleep Med 13(3):479–504, AASM, 2017
2. Obstructive sleep apnea: Diagnosis and treatment. Mayo Clinic
3. Sleep Study (Polysomnography). Cleveland Clinic
4. What Are At-Home Sleep Apnea Tests? Cleveland Clinic Health Essentials, 2022
5. Sleep Apnea. Cleveland Clinic
6. Home Sleep Apnea Test. American Academy of Sleep Medicine (Sleep Education)
7. 510(k) Summary K240929: Sleep Apnea Notification Feature (Apple Inc.). U.S. Food and Drug Administration, 2024
8. Samsung's Sleep Apnea Feature on Galaxy Watch First of Its Kind Authorized by US FDA. Samsung Newsroom, 2024
9. Chung F, Abdullah HR, Liao P. STOP-Bang Questionnaire: A Practical Approach to Screen for Obstructive Sleep Apnea. Chest 149(3):631–638, 2016
10. Continuous Positive Airway Pressure Devices & Accessories: Provider Compliance Tips. Centers for Medicare & Medicaid Services
11. Sleep studies coverage. Medicare.gov
12. Continuous positive airway pressure (CPAP) devices coverage. Medicare.gov
13. Apple Watch Series 10 features sleep apnea notifications. American Academy of Sleep Medicine, 2024