Skip to main content
Log in

The reliability and validity of the Korean version of the Pittsburgh Sleep Quality Index

  • Original Article
  • Published:
Sleep and Breathing Aims and scope Submit manuscript

Abstract

Purpose

The Pittsburgh Sleep Quality Index (PSQI) is a self-reported questionnaire that measures sleep quality during the previous month. The aims of this study were to analyze the reliability and validity of the Korean version of the PSQI (PSQI-K) and to evaluate its usefulness.

Methods

We developed the PSQI-K, which involved translating the original PSQI into Korean and then translating back into English to check its accuracy. We tested the validity of the PSQI-K on a total of 394 individuals: 261 with poor sleep (primary insomnia, n = 211; narcolepsy, n = 50) and 133 with good sleep. All subjects completed the PSQI-K, 285 had overnight nocturnal polysomnography, and 53 were randomly selected for a retest with the questionnaire after 2–4 weeks without any intervening treatment. The mean PSQI-K global scores in each group were analyzed after adjusting for age and sex.

Results

Cronbach's α coefficient for internal consistency of the total score of the PSQI-K was 0.84 which shows high reliability. Sensitivity and specificity for distinguishing poor and good sleepers were 0.943 and 0.844 using the best cutoff point of 8.5. The total and component scores of the PSQI-K for insomnia and narcolepsy were significantly higher than those for controls (p < 0.05). The test–retest correlation coefficient was 0.65 for the total score (p < 0.001). There was no significant difference between the two values using the paired t tests.

Conclusions

The PSQI-K is a reliable and valid questionnaire for evaluating sleep quality in patients with sleep disorders.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2

Similar content being viewed by others

References

  1. Carpenter JS, Andrykowski MA (1998) Psychometric evaluation of the Pittsburgh Sleep Quality Index. J Psychosom Res 45(1 Spec No):5–13

    Article  PubMed  CAS  Google Scholar 

  2. Hoch CC, Dew MA, Reynolds CF 3rd, Monk TH, Buysse DJ, Houck PR, Machen MA, Kupfer DJ (1994) A longitudinal study of laboratory- and diary-based sleep measures in healthy “old old” and “young old” volunteers. Sleep 17(6):489–496

    PubMed  CAS  Google Scholar 

  3. Kripke DF, Simons RN, Garfinkel L, Hammond EC (1979) Short and long sleep and sleeping pills. Is increased mortality associated? Arch Gen Psychiatry 36(1):103–116

    Article  PubMed  CAS  Google Scholar 

  4. Sheely LC (1996) Sleep disturbances in hospitalized patients with cancer. Oncol Nurs Forum 23(1):109–111

    PubMed  CAS  Google Scholar 

  5. Mellinger GD, Balter MB, Uhlenhuth EH (1985) Insomnia and its treatment. Prevalence and correlates. Arch Gen Psychiatry 42(3):225–232

    Article  PubMed  CAS  Google Scholar 

  6. Pilcher JJ, Ginter DR, Sadowsky B (1997) Sleep quality versus sleep quantity: relationships between sleep and measures of health, well-being and sleepiness in college students. J Psychosom Res 42(6):583–596

    Article  PubMed  CAS  Google Scholar 

  7. Sateia MJ (2009) Update on sleep and psychiatric disorders. Chest 135(5):1370–1379

    Article  PubMed  Google Scholar 

  8. Young JS, Bourgeois JA, Hilty DM, Hardin KA (2008) Sleep in hospitalized medical patients, part 1: factors affecting sleep. J Hosp Med 3(6):473–482

    Article  PubMed  Google Scholar 

  9. Buysse DJ, Reynolds CF 3rd, Monk TH, Berman SR, Kupfer DJ (1989) The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res 28(2):193–213

    Article  PubMed  CAS  Google Scholar 

  10. Aloba OO, Adewuya AO, Ola BA, Mapayi BM (2007) Validity of the Pittsburgh Sleep Quality Index (PSQI) among Nigerian university students. Sleep Med 8(3):266–270

    Article  PubMed  Google Scholar 

  11. Beck SL, Schwartz AL, Towsley G, Dudley W, Barsevick A (2004) Psychometric evaluation of the Pittsburgh Sleep Quality Index in cancer patients. J Pain Symptom Manage 27(2):140–148

    Article  PubMed  Google Scholar 

  12. Buysse DJ, Reynolds CF 3rd, Monk TH, Hoch CC, Yeager AL, Kupfer DJ (1991) Quantification of subjective sleep quality in healthy elderly men and women using the Pittsburgh Sleep Quality Index (PSQI). Sleep 14(4):331–338

    PubMed  CAS  Google Scholar 

  13. Farrahi J, Nakhaee N, Sheibani V, Garrusi B, Amirkafi A (2009) Psychometric properties of the Persian version of the Pittsburgh Sleep Quality Index addendum for PTSD (PSQI-A). Sleep Breath 13(3):259–262

    Article  PubMed  Google Scholar 

  14. Bertolazi AN, Fagondes SC, Hoff LS, Dartora EG, da Silva Miozzo IC, de Barba ME, Barreto SS (2011) Validation of the Brazilian Portuguese version of the Pittsburgh Sleep Quality Index. Sleep Med 12:70–75

    Article  PubMed  Google Scholar 

  15. Doi Y, Minowa M, Uchiyama M, Okawa M, Kim K, Shibui K, Kamei Y (2000) Psychometric assessment of subjective sleep quality using the Japanese version of the Pittsburgh Sleep Quality Index (PSQI-J) in psychiatric disordered and control subjects. Psychiatry Res 97(2–3):165–172

    Article  PubMed  CAS  Google Scholar 

  16. Shochat T, Tzischinsky O, Oksenberg A, Peled R (2007) Validation of the Pittsburgh Sleep Quality Index Hebrew translation (PSQI-H) in a sleep clinic sample. Isr Med Assoc J 9(12):853–856

    PubMed  Google Scholar 

  17. Suleiman KH, Yates BC, Berger AM, Pozehl B, Meza J (2010) Translating the Pittsburgh Sleep Quality Index into Arabic. West J Nurs Res 32(2):250–268

    Article  PubMed  Google Scholar 

  18. Tsai PS, Wang SY, Wang MY, Su CT, Yang TT, Huang CJ, Fang SC (2005) Psychometric evaluation of the Chinese version of the Pittsburgh Sleep Quality Index (CPSQI) in primary insomnia and control subjects. Qual Life Res 14(8):1943–1952

    Article  PubMed  CAS  Google Scholar 

  19. American Psychiatric Association (1994) Diagnostic criteria from DSM-IV. The Association, Washington

    Google Scholar 

  20. American Academy of Sleep Medicine (2005) The international classification of sleep disorders: diagnostic and coding manual, 2nd edn. American Academy of Sleep Medicine, Westchester

    Google Scholar 

  21. Cho YW, Lee JH, Son HK, Lee SH, Shin C, Johns MW (2011) The reliability and validity of the Korean version of the Epworth sleepiness scale. Sleep Breath (in press)

  22. Bastien CH, Vallieres A, Morin CM (2001) Validation of the Insomnia Severity Index as an outcome measure for insomnia research. Sleep Med 2(4):297–307

    Article  PubMed  Google Scholar 

  23. Backhaus J, Junghanns K, Broocks A, Riemann D, Hohagen F (2002) Test-retest reliability and validity of the Pittsburgh Sleep Quality Index in primary insomnia. J Psychosom Res 53(3):737–740

    Article  PubMed  Google Scholar 

  24. Cole JC, Motivala SJ, Buysse DJ, Oxman MN, Levin MJ, Irwin MR (2006) Validation of a 3-factor scoring model for the Pittsburgh sleep quality index in older adults. Sleep 29(1):112–116

    PubMed  Google Scholar 

Download references

Acknowledgments

Many thanks to Dr. Daniel J. Buysse, who granted us permission to use his questionnaire and who helped in our study. This work was supported by the brain research-promoting grant from Keimyung University Dongsan Medical Center.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Yong Won Cho.

Appendix

Appendix

figure a
figure b
figure c

Rights and permissions

Reprints and permissions

About this article

Cite this article

Sohn, S.I., Kim, D.H., Lee, M.Y. et al. The reliability and validity of the Korean version of the Pittsburgh Sleep Quality Index. Sleep Breath 16, 803–812 (2012). https://doi.org/10.1007/s11325-011-0579-9

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11325-011-0579-9

Keywords

Navigation