How is clinical insomnia diagnosed?

Clinical insomnia is diagnosed based on specific criteria that are considered stringent by some experts in the sleep field. According to Matthew Walker, the diagnosis involves recognizing one or more of the following symptoms that must occur several times a week for at least three months:

1. Sleep onset insomnia: Difficulties in falling asleep.
2. Sleep maintenance insomnia: Issues with staying asleep throughout the night.
3. Early morning awakenings: Waking up too early and being unable to go back to sleep.
4. Unrestorative sleep: Sleeping for a seemingly adequate number of hours but not feeling restored or refreshed.

These symptoms need to be consistent and persistent, highlighting the chronic nature of clinical-grade insomnia 1.