Sleep Study , also called a Polysomnography , is a Extansive Test Used To Diagnose Sleep Disorders . Sleep Study(polysomnography) Record Your Heartbeat , Breathing , Brainwave & Level of Oxygen In Your Blood . As well As Record The Movement of Leg & Eye During  Polysomnography . Sleep Study Typically Performed At Night , Polysomnography is Occasionally Done During The Day To Accommodate Shift Workers Who Habitually Sleep During Night . Basically Sleep Study Done In Hospital & Center But PHhealthcares Provide At Your Home . Home Sleep Apnea Testing Uses A Limited No. of Sensors of Focus Primarily on Diagnosing Obstructive Sleep Apnea (OSA)