The Pittsburg Sleep Quality Index (PSQI) and Associated Factors in Middle-school Students: A Cross-sectional Study

  • Received : 2019.10.14
  • Accepted : 2020.01.02
  • Published : 2020.01.31


Purpose: The purpose of this study was to evaluate the current level of sleep quality among Korean middle-school students using the Pittsburg Sleep Quality Index (PSQI), and to analyze the factors influencing sleep quality. Methods: The study used a descriptive cross-sectional design and a self-report questionnaire. The participants were 744 middle-school students. The questionnaire included the PSQI and health-related questions, such as the types of diseases they had been diagnosed with and the frequency of hospital admissions. The data were analyzed using the independent t-test, analysis of variance, Pearson correlation coefficients, and linear multiple regression. Results: The global PSQI score was 4.21, which indicated good sleep quality. The major factors that were associated with the sleep quality of middle-school students were the number of diseases they had been diagnosed with (β=.54, p=.001) and atopic dermatitis (β=.32, p=.001). In addition, asthma and the frequency of hospital admissions were significant factors influencing each component of the PSQI. Conclusion: The findings from this study suggest that sleep quality was associated with several health-related factors. Thus, nurses, school nurses, and nursing researchers may need to assess the health-related factors associated with adolescents' sleep quality as part of efforts to improve their sleep quality.


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