Validation of a Brief Insomnia Severity Measure in Youth Clinically Referred for Sleep Evaluation

Objectives Evaluate psychometric properties of the Pediatric Insomnia Severity Index (PISI), a brief measure of insomnia severity. Methods Clinically referred youth (n = 462; 283 males, 179 females, mean age = 7.28 +/- 2.05 years) and their caregiver(s) completed sleep evaluation including the PISI, Children's Sleep Habits Questionnaire, and sleep disorders inventory for students. Tests of reliability and validity and confirmatory factor analysis (CFA) were conducted to assess PISI psychometric properties. Exploratory analyses were conducted to examine insomnia severity by insomnia diagnosis. Results Measures of internal consistency for the PISI factor scores varied. CFA indicated that a two-factor model had optimal fit relative to a single-factor solution. Overall, convergent and discriminant validity of PISI factors were supported. Insomnia severity varied by diagnosis. Conclusions Findings provide preliminary support for the reliability and validity of the PISI within a large pediatric sample and for its clinical utility as a brief measure of insomnia severity.