top of page
Resources for the Comprehensive Geriatric Assessment based
Proactive and Personalised Primary Care of the Elderly


Insomnia Severity Index

Purpose : Quantitative measure of perception of insomnia severity, and its impact on daytime functioning


Admin time :  5 min.

User Friendly :  High

Administered by : self or GP 


Content : The ISI is a 7-item self-report questionnaire assessing the nature, severity, and impact of insomnia.

The dimensions evaluated are: severity of sleep onset, sleep maintenance, and early morning awakening problems, sleep dissatisfaction, interference of sleep difficulties with daytime functioning, noticeability of sleep problems by others, and distress caused by the sleep difficulties.

A 5-point Likert scale is used to rate each item (e.g., 0 = no problem; 4 = very severe problem), yielding a total
score ranging from 0 to 28.

The total score is interpreted as follows: absence of insomnia (0-7); sub-threshold insomnia (8-14); moderate insomnia (15-21); and severe insomnia (22-28).
Three versions are available—patient (2 week period), patient (1 month period), and clinician.


Author :  Morin, C.M. 1985

Copyright :

ISI : © Morin, C.M. (1993 and 1996)
ISI-Clinian version: © Morin, C.M. (1993, 1996, 2000, 2006)

Permission to use may be obtained from the distributors : Mapi Research Trust

pdf download transparent.png

ISI - patient 2 week

pdf download transparent.png

ISI - patient 1 month

pdf download transparent.png

ISI - clinician

link transparent 2.png

ISI- online

Insomnia Severity Index



  • reliable and valid instrument to detect cases of insomnia in the population and is sensitive to treatment response in clinical patients

  • face and content validity; correlated with sleep diaries, polysomnography, and interviews


  • ​Limited ability to differentiate primary insomnia from insomnia with comorbid psychiatric or other medical disease


Accuracy : (Morin CM, 2011) access

ISI ≥ 8    :   Sensitivity 99.4 % and specificity 91.8 %

ISI ≥ 11  :   Sensitivity 97.2 % and specificity 100 %

ISI ≥ 15  :   Sensitivity 78.1 % and specificity 100 %

Temporal Reference Period


The standard recommended time interval for completing the ISI is the “last month”; this interval corresponds to the standard period used (in DSM-IV) to make a diagnosis of insomnia.

It is also acceptable to use a shorter interval (i.e., two weeks), particularly in clinical studies assessing the impact of treatment over a shorter period of time than one month. This practice is acceptable but the time frame should be the same at each assessment period (i.e., baseline, post treatment, follow-ups).

This Tool is used in Sleep Disorders

Back To : Sleep Disorders

old man sleepless on couch
Geriatric Syndromes

Sleep Disorders is one of 4 Geriatric Syndromes


Back To : Geriatric Syndromes

bottom of page