Translation and Validation of the Pittsburgh Sleep Quality Index in the Moroccan Dialect

Abstract

Background and Objective The Pittsburgh Sleep Quality Index (PSQI) is a standardized self-administered instrument used to evaluate subjective sleep quality. The objective of our study was to translate this scale into Moroccan dialect and assess its reliability and validity among healthy and non-clinical individuals.Methods The original version of the PSQI was translated into Moroccan dialect following the standard guidelines. The final version was administered to 120 healthy volunteers (medical students, nursing staff, and doctors). The participants filled out the final questionnaire containing the PSQI translated version and the Insomnia Severity Index validated in Moroccan dialect two times within 10 days. We studied the acceptability and internal reliability of the scale by using the Cronbach’s alpha coefficient. With respect to the test-retest reliability, we used the intra-class correlation coefficient (95% confidence interval) and the kappa coefficient. Convergent validity was studied by the Pearson’s correlation coefficient between the Insomnia Severity Index total score and the PSQI total score.Results The translated version of the scale was quite acceptable. The Cronbach’s alpha coefficient was 0.61. The intraclass correlation coefficient was 0.61 (95% CI 0.491–0.707), while the kappa coefficient was 0.77. The correlations between the items of each questionnaire and its score showed good to strong positive correlations. The majority of the correlations between the components and the total score were greater than 0.30, and they ranged from 0.302 to 0.481. The analysis of convergent validity showed significant correlations between the Insomnia Severity Index score and the global score of the translated the PSQI.Conclusions The Moroccan version of PSQI shows good validity and reliability compared to the original English version among the general population. We should further test its validity in patients with psychiatric disorders.