Insomnia Severity Index (ISI): Understanding the Score
Understand the seven-item ISI, its 0–28 score and how it describes insomnia symptoms. Information only; the Arabic questionnaire is not available here.
Information only; questionnaire not currently available here.
What ISI measures
The seven-item Insomnia Severity Index describes sleep difficulties, dissatisfaction and daytime impact. Total scores range from 0 to 28.
Using the result
The score may support symptom monitoring but does not establish the cause or diagnose every sleep disorder. Note when the problem began, sleep and waking times and daytime effects. An irregular work schedule and inability to sleep despite sufficient opportunity require different contextual questions.
Evidence and availability
Research supports assessing insomnia symptoms and treatment-related change in studied populations. Interpretation depends on the version and setting. This page is informational. The Arabic questionnaire is not offered here until appropriate electronic-publication permission is completed.