If you’ve taken a home sleep test or are considering one, you might wonder: how does it compare to an in-lab sleep study? Both are used to diagnose sleep disorders, especially obstructive sleep apnea (OSA), but they differ significantly in data depth, context, and accuracy.
This guide breaks down the differences—what each test records, when to choose which, and why understanding your numbers matters for treatment success.
What Is a Home Sleep Test?
A home sleep apnea test (HSAT) is a simplified version of an overnight sleep study. It allows you to sleep in your own bed while wearing a few compact sensors that record limited data, usually over 1–3 nights.
Most HSAT kits include:
- A finger sensor for oxygen levels and heart rate
- A nasal cannula for airflow detection
- A belt around the chest or abdomen to monitor breathing effort
- Sometimes a position or snore sensor
Some tests also record body movement or audio, but they do not track brain waves, eye movements, or precise sleep stages. That means they can’t distinguish between REM and non-REM sleep—a key part of more complex diagnoses.
What Is an In-Lab Sleep Study?
A polysomnography (PSG) in a clinical sleep center is a far more detailed test. In addition to what an HSAT records, it monitors:
- EEG brain activity
- Eye movements (EOG)
- Chin and jaw muscle tone (EMG)
- Leg movement
- Video monitoring for sleepwalking or limb movements
- Arousals and sleep architecture—not just breathing issues
This level of data allows doctors to diagnose central sleep apnea, REM behavior disorder, narcolepsy, and more. It’s also used to calibrate CPAP settings and verify treatment response.
If you’re deciding between the two, it comes down to how much data your condition demands.
Comparing the Numbers: What the Metrics Mean
The most important takeaway from any sleep test—whether at home or in the lab—is your Apnea-Hypopnea Index (AHI).
The AHI represents how many times per hour your breathing is paused or reduced for 10 seconds or more. It’s categorized as:
- Normal: <5 events/hour
- Mild apnea: 5–15 events/hour
- Moderate apnea: 15–30 events/hour
- Severe apnea: 30+ events/hour
Here’s where the difference lies: AHI from a home test is based on total recording time (from when you turn the device on to off), while AHI from a lab test is based on actual sleep time—measured by EEG.
That means if you were awake for much of the night during a home test, your AHI could be falsely low because the device assumes you were sleeping the entire time.
American Academy of Sleep Medicine guidelines acknowledge this and recommend lab testing for people with unclear or borderline HSAT results.
Other Metrics That Differ Between Tests
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Oxygen Desaturation Index (ODI)
Both home and lab tests track your oxygen dips, but lab-grade oximeters are more accurate and log each desaturation more precisely. Low oxygen during sleep is tied to cardiovascular risks, so accurate ODI matters.
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Sleep Efficiency & Architecture
Only in-lab tests can measure how much of the night you actually spend asleep, how long it takes to fall asleep, and how much of your time is spent in REM, light, and deep sleep. These details can reveal conditions like narcolepsy, insomnia with short sleep duration, or periodic limb movement disorder.
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Arousals
Frequent awakenings from sleep—often not remembered by the patient—can indicate sleep fragmentation, even when AHI is normal. Lab studies measure this via brain activity and muscle tone, which HSATs do not.
When Home Tests Work Well
For many patients, especially those with classic OSA symptoms like snoring, gasping at night, and daytime sleepiness, a home test is enough. It’s:
- Less expensive
- More convenient
- Easier to schedule
If your AI screening, such as our 60-second facial scan, flags you as high risk for obstructive sleep apnea, a home test may be the first recommended step.
But if your results are borderline, or symptoms don’t line up with AHI, further testing may be needed.
When a Sleep Lab Is Better
In-lab testing is strongly recommended if:
- Your home test is inconclusive or negative, but symptoms persist
- You have risk factors for central sleep apnea (e.g., heart failure, opioid use)
- You’ve been diagnosed but aren’t responding to CPAP
- You show signs of narcolepsy or parasomnias
- You have coexisting insomnia and sleep maintenance issues
If your doctor suspects complex or mixed apnea, lab testing helps separate obstructive and central events to guide better treatment.
Can Both Be Used Together?
Yes—and often they are. A common pathway looks like this:
- Initial AI-based risk screening (e.g., via facial scan or STOP-Bang)
- Home test to confirm obstructive sleep apnea
- Lab test for fine-tuning therapy, diagnosing additional conditions, or evaluating residual symptoms
This hybrid approach reduces costs and patient burden while maintaining clinical accuracy.
What About Insurance?
Most insurance plans—including Medicare—cover both home and in-lab testing when medically necessary. Home tests are often pre-authorized faster, but a lab test may be required if the home test doesn’t offer clear results.
Your provider can determine what’s medically appropriate—and we handle the paperwork and insurance coordination throughout the process.
The Bottom Line
Sleep testing isn’t one-size-fits-all. While home tests are convenient and helpful for straightforward cases of obstructive sleep apnea, they don’t replace the detailed insight a sleep lab provides.
Understanding the limitations of home tests—especially how they calculate AHI—can help you make informed decisions about your diagnosis and care.
If you’ve had a home test but still feel unwell, or your symptoms don’t match the results, don’t stop there. Your sleep story might still be incomplete.
