The Insomnia Severity Index (ISI) is a widely used, concise screening tool designed to help individuals and professionals understand the severity and impact of insomnia. This self-report questionnaire provides a standardized method for evaluating sleep difficulties and gaining insight into sleep patterns.
The Insomnia Severity Index Explained
The Insomnia Severity Index was developed by Dr. Charles M. Morin and his colleagues, becoming a recognized measure for assessing insomnia. This tool consists of seven items, designed to capture a comprehensive picture of an individual’s perceived sleep problems. The ISI is a reliable and valid instrument, demonstrating strong internal consistency.
The index assesses various aspects of insomnia, including difficulties with sleep onset, maintaining sleep, and early morning awakenings. It also evaluates satisfaction with sleep, interference with daily functioning, and distress caused by these difficulties. It correlates with objective measures like sleep diaries and polysomnography, supporting its utility in understanding subjective sleep experiences.
Completing and Scoring the Index
Each of the seven items on the Insomnia Severity Index is rated on a 5-point Likert scale. Values range from 0 to 4, where 0 indicates “no problem” and 4 signifies a “very severe problem.” For instance, questions ask about the severity of difficulty falling asleep or waking too early.
After rating all seven items, the scores are summed to yield a total score, which can range from 0 to 28. The assessment asks individuals to reflect on their sleep patterns over the past two weeks or month.
Understanding Your Score
The total score obtained from the Insomnia Severity Index provides insight into the perceived severity of sleep difficulties. A score between 0 and 7 suggests an absence of clinically significant insomnia. Individuals scoring in this range typically report satisfactory sleep patterns.
Scores from 8 to 14 indicate subthreshold insomnia, meaning there are mild sleep disturbances present. A score between 15 and 21 points to moderate insomnia, suggesting significant sleep disruptions that may impact daily functioning. Finally, a score ranging from 22 to 28 indicates severe insomnia, often associated with substantial impairments to quality of life. These scores are intended for self-assessment and to facilitate discussions with a healthcare professional, rather than for self-diagnosis.
Finding the ISI Form
The Insomnia Severity Index form is widely available for individuals seeking to assess their sleep. Printable PDF versions are available on reputable sleep clinic websites, academic research portals, or mental health resource platforms. It is helpful to seek out official or validated versions to ensure accuracy.
The form serves as a valuable self-assessment tool, offering a structured way to quantify sleep concerns. While it provides a clear indication of insomnia severity, discussing your results with a healthcare provider is recommended. This allows for a comprehensive evaluation and helps guide appropriate next steps for managing sleep health.