Insomnia Severity Index (ISI): Score and Bands

What it measures

The Insomnia Severity Index (Morin) is a seven-item self-report measure of the current severity of sleep problems over the last 2 weeks. It covers difficulty falling asleep, difficulty staying asleep, waking too early, satisfaction with the current sleep pattern, how noticeable the problem is to others, how worried or distressed the patient is about it, and how much it interferes with daytime functioning. It is a screening and outcome-tracking measure, not a stand-alone diagnosis. Interpret it alongside the history, a sleep diary, and evaluation for medical, psychiatric, circadian and substance factors.

Items and scoring

Each item is scored 0 to 4, and the response wording differs by item: items 1–3 run from None to Very severe, item 4 from Very satisfied to Very dissatisfied, and items 5–7 from Not at all to Very much. The total is the sum of the seven items, from 0 to 28. The tool assigns a band only after all seven items are answered.

Score	Interpretation
0–7	No clinically significant insomnia
8–14	Subthreshold insomnia
15–21	Clinical insomnia (moderate severity)
22–28	Clinical insomnia (severe)

The tool's scoring note adds that a community screening cut-off of 10 or more is often used to detect insomnia, that treatment response is commonly defined as a reduction of 6 or more points, and that remission is commonly defined as a total below 8.

Interpreting the result

Each band carries a suggested next step. Subthreshold scores point to sleep-hygiene and stimulus-control education with brief CBT-I strategies. Moderate clinical insomnia points to first-line CBT-I and a search for contributing factors. Severe clinical insomnia points to structured CBT-I with or without a pharmacologic adjunct, plus assessment of comorbidities and safety. A link opens the site's CBT-I treatment module.

What the report includes

Generate Report copies a plain-text summary with the date, total out of 28, the band and suggested action, each item with its numeric and verbal response, the scoring note and three references: Morin 1993 (Insomnia: Psychological Assessment and Management), Bastien, Vallieres and Morin 2001 (Sleep Med), and Morin, Belleville, Belanger and Ivers 2011 (Sleep). If any item is unanswered, the report marks the score as incomplete and leaves it unclassified.