How is delayed sleep phase diagnosed?

History, sleep study: Delayed sleep phase syndrome is a type of insomnia caused by delaying going to bed, which causes one to go to sleep later and later. Once they go to sleep, they sleep normally. This is diagnosed by taking a careful history and possibly doing a sleep study. Treatment is improved sleep hygiene to get to bed at a consistent time. This resets the sleep cycle to the desired time.

Sleep log: Usually the diagnostic workup begins with a 7 day sleep log and a questionnaire that determines your best time of performance. Medical, other sleep disorders and psychiatric illnessness must also be ruled out. A sleep study can also be helpful.

By history: Delayed sleep phase occurs when the circadian rhythm is out of phase with the sleep cycle. Staying up late on a regular basis makes you sleep in late to get enough sleep. It's frequently seen in young adults. Getting a good history is usually enough for diagnosis.