Comparability of sleep questionnaires and the possibility of binary division by the insomnia severity index

Background. Sleep disturbances significantly reduce life quality. Insomnia is one of the most common symptoms of menopause. Various questionnaires, such as the Insomnia Severity Index (ISI), the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS) are considered for subjective quality assessment. Studies often use one or two questionnaires, making it difficult to compare results. Further complications are caused by differences in the number of groups which the sample is divided based on the results. To successfully compare the results of studies using different questionnaires, it is necessary to correlate the questionnaire results and standardize the groupings.

The aim. To compare sleep questionnaires and determine the most appropriate cut-off point for binary distribution for ISI.

Methods. Ninety-six menopausal women participated in the study. Participants taking melatonin, suffering from diabetes or cancer, or chronic diseases on acute stage, were excluded. Participants completed the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), and the Epworth Sleepiness Scale (ESS). Results were assessed and women were grouped according to standard protocols for these questionnaires. A comparison of the ISI questionnaire results (based on the four-group questionnaire modification) with the PSQI and ESS to determine the most appropriate cut-off point for obtaining a binary distribution was performed using Cohen's kappa.

Results. The ISI correlates with the PSQI. The ESS should be considered as an assessment of another aspect of sleep disturbance. The cut-off point at which the ISI and PSQI groups similarity is higher was 10 points.

Conclusion. Defining a specific cut-off point allows to use the ISI questionnaire when binary division is necessary.

1. Kovalzon VM. Fundamentals of Somnology: Physiology and Neurochemistry of the Sleep-Wake Cycle. Knowledge Laboratory; 2017. (In Russ.).

2. Kolesnikova LI, Kolesnikov SI, Madaeva IM, Semenova NV. Ethnogenetic and Molecular-Metabolic Aspects of Sleep Disorders in Menopause. Russian Academy of Sciences; 2019.

3. Edinger JD, Bonnet MH, Bootzin RR, et al. Derivation of Research Diagnostic Criteria for Insomnia: Report of an American Academy of Sleep Medicine Work Group. Sleep. 2004; 27(8): 1567-1596. doi: 10.1093/sleep/27.8.1567

4. Poluektov MG, Buzunov RV, Volel BA, et al. Clinical Somnology. MedCongress; 2020. (In Russ.).

5. Madaeva IM, Kolesnikova LI, Solodova EI, Semenova NV. Menopause and sleep disturbances. Bulletin of the VSRC SB RAMS. 2012; 84(2-2): 173-177. (In Russ.).

6. Madaeva IM, Semenova NV, Astafyev VA, Druzhinina EB, Labigina AB. Sleep features in menopausal women (literature review). Acta Biomed Sci. 2018; 3(3): 75-81. (In Russ.). doi: 10.29413/ABS.2018-3.3.11

7. Madaeva IM, Semenova NV, Kolesnikova LI, Kolesnikov SI. Aging and cognitive disorders from the somnology's viewpoint. Advances in Gerontology. 2021; 34(2): 195-201. (In Russ.). doi: 10.34922/AE.2021.34.2.002

8. McPhillips MV, Petrovsky DV, Lorenz R, et al. Treatment Modalities for Insomnia in Adults Aged 55 and Older: A Systematic Review of Literature from 2018 to 2023. Curr Sleep Medicine Rep. 2024; 10(2): 232-256. doi: 10.1007/s40675-024-00285-w

9. Redeker NS, Yaggi HK, Jacoby D, et al. Cognitive behavioral therapy for insomnia has sustained effects on insomnia, fatigue, and function among people with chronic heart failure and insomnia: the HeartSleep Study. Sleep. 2022; 45(1): zsab252. doi: 10.1093/sleep/zsab252

10. Michaud AL, Zhou ES, Chang G, Recklitis CJ. Validation of the Insomnia Severity Index (ISI) for identifying insomnia in young adult cancer survivors: comparison with a structured clinical diagnostic interview of the DSM-5 (SCID-5). Sleep Medicine. 2021; 81: 80-85. doi: 10.1016/j.sleep.2021.01.045

11. Van Straten A, Weinreich KJ, Fabian B, et al. The Prevalence of Insomnia Disorder in the General Population: A Meta-Analysis. Journal of Sleep Research. 2025; 34(5): e70089. doi: 10.1111/jsr.70089

12. Morin CM, Belleville G, Belanger L, Ivers H. The Insomnia Severity Index: Psychometric Indicators to Detect Insomnia Cases and Evaluate Treatment Response. Sleep. 2011; 34(5): 601-608. doi: 10.1093/sleep/34.5.601

13. Bastien C. Validation of the Insomnia Severity Index as an outcome measure for insomnia research. Sleep Medicine. 2001; 2(4): 297-307. doi: 10.1016/S1389-9457(00)00065-4

14. Ellis JG, Perlis ML, Espie CA, et al. The natural history of insomnia: predisposing, precipitating, coping, and perpetuating factors over the early developmental course of insomnia. SLEEP. 2021; 44(9): zsab095. doi: 10.1093/sleep/zsab095

15. Kolesnikova LI, Semenova NV, Solodova EI, Madaeva IM. Oxidative stress in women with insomnia in different stages of menopause. Therapeutic archive. 2017; 89(8): 50-56. (In Russ.). doi: 10.17116/terarkh201789850-56

16. Gonçalves MT, Malafaia S, Moutinho Dos Santos J, Roth T, Marques DR. Epworth sleepiness scale: A meta-analytic study on the internal consistency. Sleep Medicine. 2023; 109: 261-269. doi: 10.1016/j.sleep.2023.07.008

17. Sadeghniiat-Haghighi K, Montazeri A, Khajeh-Mehrizi A, Nedjat S, Aminian O. The Insomnia Severity Index: cross-cultural adaptation and psychometric evaluation of a Persian version. Qual Life Res. 2014; 23(2): 533-537. doi: 10.1007/s11136-013-0489-3

18. Scharf MT. Reliability and Efficacy of the Epworth Sleepiness Scale: Is There Still a Place for It? NSS. 2022; 14: 2151-2156. doi: 10.2147/NSS.S340950

19. Sunwoo BY, Kaufmann CN, Murez A, et al. The language of sleepiness in obstructive sleep apnea beyond the Epworth. Sleep Breath. 2023; 27(3): 1057-1065. doi: 10.1007/s11325-022-02703-1

20. Wang L, Fang X, Xu C, et al. Epworth sleepiness scale is associated with hypothyroidism in male patients with obstructive sleep apnea. Front Endocrinol. 2022; 13: 1010646. doi: 10.3389/fendo.2022.1010646

21. Ozen F, Yegin Z, Saglam ZA, Yavlal F, Koc H, Ulasoglu C. Association analysis of Epworth Sleepiness Scale (ESS) scores with serotonin transporter (5-HTT-LPR, 5-HTT-VN-TR) and circadian (PER3-VNTR) genes. Sleep Sci. 2022; 15(Spec 1): 110-115. doi: 10.5935/1984-0063.20220003

22. Riemann D, Baglioni C, Bassetti C, et al. European guideline for the diagnosis and treatment of insomnia. Journal of Sleep Research. 2017; 26(6): 675-700. doi: 10.1111/jsr.12594