Insomnia Test — Insomnia Severity Index (ISI)

What it measures

This check uses the Insomnia Severity Index (ISI), a validated 7-item questionnaire designed by Bastien, Vallières, and Morin (2001) to measure the nature, severity, and impact of insomnia. It covers difficulty falling asleep, staying asleep, and waking too early, as well as your satisfaction with sleep, the impact on daily functioning, how noticeable the problem is to others, and your level of distress. Total scores range from 0 to 28.

How it works

You rate seven aspects of your sleep over the past two weeks on a five-point severity scale from None to Very severe. We sum your answers into a score out of 28 and place it in one of four clinically validated bands. The whole check takes under two minutes.

Tips for an accurate result

• 1Keep a consistent wake time — Getting up at the same time every day — including weekends — is one of the most powerful ways to reset your body clock and reduce time awake in bed.
• 2Bed is for sleep — Avoid working, scrolling, or watching television in bed. Over time, your brain learns to associate the bedroom with wakefulness, making it harder to switch off.
• 3Cut caffeine after midday — Caffeine has a half-life of roughly five to six hours, meaning an afternoon coffee can still be active in your system at midnight.
• 4Try stimulus control — Only go to bed when you are genuinely sleepy. If you are not asleep within about 20 minutes, get up and do something calm in dim light until you feel sleepy again. This is a core technique in CBT-I.
• 5Limit alcohol as a sleep aid — Alcohol may help you fall asleep faster but disrupts the second half of the night, reducing restorative deep sleep and causing earlier waking.