Sleep studies are tests performed in a sleep center that measure physiological aspects of sleep. They are typically performed in a sleep center, and are used to diagnose sleep disorders including insomnia, hypersomnia, sleep apnea and narcolepsy.

A number of activities are measured during a sleep study, such as electrical activity of the brain and heart, oxygen saturation and leg muscle movement.

Before the sleep study, patients may be required to maintain a sleep diary in which they record their sleep patterns. Some ways to prepare for the study are avoiding alcohol and caffeine and packing a bag with personal items needed for an overnight stay.

During the sleep study, electrodes and other sensors are usually placed on the scalp, sides of the head and under the chin, chest and legs. A sensor is typically placed under the nose and mouth and belts are placed around the chest and abdomen. A clip is placed on a finger.

Patients go to sleep and are monitored throughout the night by a technician and video cameras. After the study is completed, the results are tabulated and may be sent to the physician or other health professional who referred the patient to the sleep center.