Level 1, 2 and 3 sleep studies: which one do you actually need?
Last updated: 2026-09-06
Quick answer
Sleep studies come in levels by how much they record. Level 1 is an attended overnight lab study (most channels). Level 3 is an unattended home test measuring airflow, effort, oxygen and heart rate — enough to diagnose obstructive sleep apnea in typical cases. SleepEase provides Level 3 home testing for ₹2,500.
What is a Level 1 sleep study?
A Level 1 study is full polysomnography (PSG) done overnight in a sleep lab with a technician present. It records brain waves (EEG), eye movements, muscle activity, airflow, breathing effort, oxygen and heart rhythm — the most complete picture, used for complex or uncertain cases.
What is a Level 2 sleep study?
A Level 2 study records a similar broad set of channels including EEG, but is unattended — the device is set up and you sleep at home or in a room without a technician watching. It is less common in routine practice.
What is a Level 3 home sleep test?
A Level 3 test (home sleep apnea test, HSAT) focuses on breathing: nasal airflow, chest/abdominal effort, oxygen saturation (SpO₂), heart rate, snoring and body position. It does not record brain waves, so it measures breathing events per hour of recording rather than per hour of confirmed sleep. For people with clear symptoms of obstructive sleep apnea, it is clinically validated and widely recommended as the first test.
Which level do most people need?
If your main problem is loud snoring, gasping or witnessed pauses, and daytime sleepiness, a Level 3 home test is usually the sensible first step. Your doctor may escalate to a Level 1 lab study if the home test is inconclusive or if a non-breathing sleep disorder is suspected.
Related: sleep study pricing · cost in Kerala · CPAP & BiPAP rental · home test in Kozhikode · book a test
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