Italian Validation of the Pittsburgh Sleep Quality Index (PSQI) in a Population of Healthy Children: A Cross Sectional Study

Background: Sleep disorders are one of the most discussed topics in scientific literature every year. Although they are one of the most studied topics, in both adults and children, knowledge of sleep disorders and their treatment is still not completely clear, and there is a need to deepen and analyze these disorders on a country-by-country basis. However, research in the Italian literature reveals a scarce quantity of tools to evaluate sleep quality in children. The Pittsburgh Sleep Quality Index (PSQI) is probably the most commonly used retrospective self-assessment questionnaire in the adult population. Purpose: We aimed to validate and analyze the psychometric characteristics of this tool in order to detect and explore the presence of sleep disorders in a healthy Italian population of children throughout the country. Methods: Individuals aged between 3 and 16 years without symptoms of insomnia were included in this study. The reliability and construct validity of the PSQI were assessed according to Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines. Results: We enrolled 222 individuals in this study (mean age 11 years). The PSQI demonstrated good internal consistency (Cronbach's alpha = 0.719). Test-retest reliability was assessed on a randomized subgroup of the sample (n = 35). The PSQI showed good test-retest reliability with an intraclass correlation coefficient of 0.829 for the total score (95% confidence interval: 0.662-0.914). The Pearson correlation coefficient, used for construct validity, showed a statistically significant positive correlation with the Sleep Disturbance Scale for Children (SDSC). Conclusion: The PSQI proved to be a very reliable and valid tool to investigate sleep experiences in children.