Insomnia Severity Index (ISI) - Online Assessment Tool

The Insomnia Severity Index (ISI) is a scientifically validated 7-item screening tool designed to assess the severity and impact of insomnia symptoms. Developed by Bastien, Vallières, and Morin, this brief questionnaire evaluates sleep difficulties over the past two weeks and their impact on daily functioning.

What is the Insomnia Severity Index?

The ISI is a widely used clinical instrument that measures the perceived severity of insomnia symptoms, including:

• Difficulty falling asleep
• Difficulty staying asleep
• Early morning awakening problems
• Sleep pattern satisfaction
• Interference with daily functioning
• Noticeability to others
• Worry and distress about sleep problems

This assessment takes approximately 5 minutes to complete and provides valuable insights into the nature and severity of sleep disturbances.

Clinical Applications

Healthcare professionals use the ISI to:

• Screen for insomnia in primary care and sleep medicine settings
• Monitor treatment progress by comparing scores over time
• Assess functional impact of sleep problems on daily life
• Guide treatment decisions based on severity levels
• Research sleep disorders in clinical and academic settings

The ISI has been validated across diverse populations, including adults aged 17 to 84 years with various sleep disorders.

Understanding Your ISI Score

The ISI produces a total score ranging from 0 to 28, with higher scores indicating more severe insomnia symptoms:

Score Interpretation

• 0-7: No clinically significant insomnia

  • Minimal sleep difficulties that don’t significantly impact daily functioning
  • Generally indicates normal sleep patterns

• 8-14: Subthreshold insomnia

  • Mild sleep difficulties that may benefit from basic interventions
  • Sleep hygiene education and lifestyle modifications may be helpful

• 15-21: Clinical insomnia (moderate severity)

  • Moderate insomnia that significantly impacts daily functioning
  • Warrants clinical attention and structured treatment approaches

• 22-28: Clinical insomnia (severe)

  • Severe insomnia requiring comprehensive clinical assessment
  • May benefit from specialized sleep medicine evaluation and intensive treatment

Scientific Validation

The ISI demonstrates strong psychometric properties:

• Internal consistency: Cronbach’s alpha = 0.74
• Test-retest reliability: Stable scores over time
• Content validity: Comprehensive coverage of insomnia symptoms
• Concurrent validity: Strong correlations with other sleep measures
• Clinical sensitivity: Effective discrimination between insomnia severity levels

Research has shown item-total correlations ranging from 0.36 to 0.54, indicating good internal structure and reliability.

Who Can Benefit from the ISI?

The Insomnia Severity Index is appropriate for:

• Adults experiencing sleep difficulties
• Patients in primary care settings
• Individuals in sleep medicine clinics
• Research participants in sleep studies
• People monitoring their sleep improvement over time

Treatment Considerations

ISI scores can help guide treatment approaches:

• Subthreshold scores may respond to sleep hygiene education and cognitive-behavioral techniques
• Moderate scores often benefit from structured CBT for insomnia (CBT-I)
• Severe scores may require comprehensive evaluation for underlying sleep disorders

Using Survey.Doctor’s ISI Assessment

Our digital version of the ISI offers:

• Instant scoring with immediate interpretation
• Secure data storage with HIPAA compliance
• Progress tracking for monitoring improvement over time
• Professional reporting for healthcare providers
• Research-grade accuracy maintaining the original instrument’s validity

Important Considerations

While the ISI is a valuable screening tool, it should be interpreted within the context of a comprehensive clinical evaluation. The assessment focuses on subjective sleep experiences and should be complemented by:

• Detailed sleep history
• Sleep diary monitoring
• Medical history review
• Consideration of underlying conditions

Scores alone do not constitute a diagnosis and should always be interpreted by qualified healthcare professionals familiar with sleep medicine.

Research and Development

The ISI continues to be extensively used in sleep research, contributing to our understanding of:

• Insomnia prevalence and patterns
• Treatment efficacy in clinical trials
• Sleep disorder comorbidities
• Population-based sleep health studies

Its brief format and robust psychometric properties make it an ideal tool for both clinical practice and research applications.

Take the ISI assessment today to better understand your sleep patterns and their impact on your daily life. Our secure platform ensures your privacy while providing you with valuable insights into your sleep health.