Purpose: The purpose of this study was to translate the Insomnia Severity Index (ISI) into Arabic (Fusha dialect), and obtain preliminary reliability and validity estimates for the translated version.
Background: Arabic populations experience sleep problems that interfere with their vitality and quality of life. The ISI was established to screen for insomnia in both clinical and research situations.
Design: This study used a descriptive correlational design. The ISI was translated into Arabic using the back-translation method and compared with three other sleep measures: the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale, and the Vitality Subscale from the Medical Outcomes Study Short Form-36. These measures were administered to 35 healthy Arabic bilingual participants from three community locations.
Findings: The mean ISI score was 9.2 (SD = 5.8; range 0-20). Internal consistency reliability was 0.84. The correlations between the total ISI score and the single items ranged from 0.49 to 0.92 (p < .01). In terms of convergent validity, the total ISI score showed a strong positive correlation with the Pittsburgh Sleep Quality Index global score (r = 0.76, p < .001) and a moderate, negative correlation with vitality (r = -0.38, p =.026).
Conclusions: The translated ISI demonstrated adequate reliability and validity. The translated ISI needs further testing in a larger sample of both clinical and healthy Arabic populations in their own countries.
Clinical relevance: Preliminary psychometric estimates show that the translated ISI is reliable and valid in this community-dwelling Arabic sample. The translated ISI allows for Arabic researchers to screen for insomnia and plan for future intervention studies.
© 2011 Sigma Theta Tau International.