Screening scores
Insomnia Severity Index Score Interpreter
The Insomnia Severity Index (ISI), developed by Dr. Charles Morin, is a seven item questionnaire about the severity and impact of insomnia over the past two weeks. Each item is scored 0 to 4, for a total of 0 to 28. It is copyrighted, so this page does not reproduce the questions; it interprets a total you have from a clinician or an authorized copy.
How it works
The total is compared with the published ISI bands: 0 to 7 no clinically significant insomnia, 8 to 14 subthreshold insomnia, 15 to 21 clinical insomnia of moderate severity, and 22 to 28 severe clinical insomnia.
Example
A total of 17 falls in the 15 to 21 band, clinical insomnia of moderate severity.
Assumptions and limits
- This is a screening and education aid, not a diagnosis. Only a clinician, usually with a sleep test, can diagnose a sleep disorder.
- The ISI is copyright Charles M. Morin; only its published scoring bands are used here.
- In treatment studies a drop of about 8 points or more is often treated as a meaningful improvement and a score under 8 as remission.
- Insomnia can be linked to depression, anxiety, pain, sleep apnea, restless legs and medicines, which a clinician can assess.
Frequently asked questions
What ISI score means I should get help?
A score of 15 or higher falls in the clinical insomnia range. Even a subthreshold score is worth raising if poor sleep affects your days. Cognitive behavioral therapy for insomnia (CBT-I) is the recommended first line treatment for chronic insomnia in adults.
How long does insomnia have to last to be chronic?
Chronic insomnia disorder is generally defined as trouble falling or staying asleep at least three nights a week for at least three months, with daytime effects, despite adequate opportunity to sleep.
Can I take the ISI online?
Clinics and research studies use authorized copies. This page only interprets a total score, because the questionnaire itself is copyrighted.
Sources
Tools and screening scores are general information. They cannot diagnose or rule out a sleep disorder. Read our medical disclaimer.