In order for a split night study to be performed, a patient should meet certain qualifying criteria. Medicare and Medicaid guidelines stipulate that in order for a patient to qualify for treatment of their sleep disorder with CPAP therapy, they must undergo an attended sleep study and have a minimum of two hours of recorded sleep with an apnea/hypopnea index of equal to or greater than 15 events per hour. In other words, a patient should have cessation of breathing occurring at least 15 times an hour during two hours of recorded sleep. Waking periods, or periods that the patient may be in the bathroom are not included in the two hour period. In a sleep lab setting, it is not always possible for a patient to obtain the minimum two hours of sleep prior to 1:00 in the morning. This is typically the cut-off time, as there needs to be sufficient time allowed for adequate application and titration of the CPAP therapy.