Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

OBJECTIVE: The Sleep Condition Indicator (SCI) and Insomnia Severity Index (ISI) are commonly used instruments to assess insomnia. We evaluated their psychometric properties, particularly their discriminant validity against structured clinical interview (according to DSM-5 and ICSD-3), and their concurrent validity with measures of sleep and daytime functioning. METHODS: A total of 158 young adults, 16% of whom were diagnosed with DSM-5 insomnia disorder and 13% with ICSD-3 Chronic Insomnia by structured interview, completed the ISI and SCI twice in 7-14 days, in addition to measures of sleep and daytime function. RESULTS: The Chinese version of the SCI was validated with good psychometric properties (ICC = 0.882). A cutoff of ≥8 on the ISI, ≤5 on the SCI short form, and ≤21 on the SCI achieved high discriminant validity (AUC > 0.85) in identifying individuals with insomnia based on both DSM-5 and ICSD-3 criteria. The SCI and ISI had comparable associations with subjective (0.18 < r < 0.51) and actigraphic sleep (0.31 < r < 0.43) and daytime functioning (0.34 < r < 0.53). CONCLUSION: The SCI, SCI short form, and ISI were found to correctly identify individuals with DSM-5- and ICSD-3-defined insomnia disorder. Moreover, they showed good concordance with measures of daytime dysfunction, as well as subjective and objective sleep. The SCI and ISI are recommended for use in clinical and research settings.

Original publication

DOI

10.1016/j.sleep.2016.05.019

Type

Journal article

Journal

Sleep Med

Publication Date

05/2017

Volume

33

Pages

76 - 81

Keywords

Actigraphy, Psychometrics, Sleep assessment, Sleep diary, Sleep–wake disorders