What is the Insomnia Severity Index (ISI)?
The Insomnia Severity Index (ISI) is a brief, self-report questionnaire designed to assess the nature, severity, and impact of insomnia. It is one of the most widely used and scientifically validated tools by sleep clinics and doctors worldwide to diagnose clinical insomnia.
Created by Dr. Charles Morin in 1993, the test evaluates both the nighttime symptoms (like trouble falling asleep or staying asleep) and the daytime consequences of sleep deprivation (like mood disturbances and cognitive impairment).
How to Interpret Your Insomnia Test Score
The quiz consists of 7 questions, each scored on a scale from 0 to 4. Your total score will range from 0 to 28. Here is what your score means:
- 0–7 (No Clinically Significant Insomnia): Your sleep is generally healthy. Any occasional sleep disturbances are normal and not a cause for clinical concern.
- 8–14 (Subthreshold Insomnia): You have mild to moderate sleep issues. While you might not need clinical treatment, optimizing your sleep hygiene and using our bedtime calculator can help get you back on track.
- 15–21 (Clinical Insomnia - Moderate Severity): Your sleep problems are noticeable and are likely interfering with your daily life. It is recommended to explore structural changes like Cognitive Behavioral Therapy for Insomnia (CBT-I).
- 22–28 (Clinical Insomnia - Severe): You are experiencing severe sleep disturbances that heavily impact your quality of life, mental health, and physical well-being. Please consult a healthcare professional or a board-certified sleep specialist.
What to Do if You Have High Insomnia Scores
If your score indicates moderate to severe insomnia, do not panic. Insomnia is highly treatable. Here are the most effective, evidence-based steps you can take:
- Look into CBT-I: Cognitive Behavioral Therapy for Insomnia is the first-line treatment recommended by the American College of Physicians, even before sleep medication.
- Fix Your Sleep Window: Going to bed early to "catch up on sleep" often makes insomnia worse. Use our Wake-Up Time Calculator to establish a strict, consistent rising time.
- Manage Your Sleep Debt Carefully: Trying to aggressively pay back missed sleep by sleeping in on weekends disrupts your circadian rhythm. Calculate your true deficit with our Sleep Debt Calculator and pay it back in small increments.
- Consult a Doctor: If your insomnia persists for more than 3 months, it is considered chronic. A doctor may check for underlying issues like sleep apnea or thyroid problems.