How severe is your insomnia?
The ISI (Insomnia Severity Index) was developed by Morin (1993) and validated by Bastien et al. (2001). It is the most widely used self-report scale to assess insomnia severity and its impact on daily functioning.
It evaluates the three core dimensions of insomnia: difficulty falling asleep, difficulty staying asleep, and early morning awakening. Plus the impact on satisfaction with sleep, daily functioning, quality of life, and worry about sleep.
Important limitations: the score reflects the last 2 weeks. A high score is a signal to explore further, not a diagnosis. The ISI does not replace a sleep study, which is necessary to rule out conditions such as sleep apnea.
ISI Test — Insomnia Severity Index
Developed by Morin (1993) and validated by Bastien et al. (2001), the ISI is the reference scale to assess insomnia severity and its impact on daily functioning.
Validated by: Bastien, Vallières & Morin (2001); Morin (2011)
If your result concerns you
A test orients you. A conversation brings clarity.
Frequently asked questions
Is the ISI a diagnosis of insomnia?
No. The ISI is a screening tool, not a diagnostic instrument. A high score indicates that a professional evaluation is worth it, but only a sleep specialist can establish a diagnosis.
What is the difference between acute and chronic insomnia?
Acute insomnia lasts less than 3 months and is usually triggered by a stressful event. Chronic insomnia lasts more than 3 months and persists at least 3 nights per week.
Can I use the ISI to track treatment progress?
Yes. Many clinicians use the ISI as a quick pre/post measure. If you are in therapy, taking it every 2-4 weeks can help you see the progress objectively.
Are my answers stored?
No. The test runs entirely in your browser.