Psychometric properties of the Insomnia Severity Index in Ethiopian adults with substance use problems

Abstract

This study investigated the psychometric properties of the Insomnia Severity Index (ISI) in substance-using Ethiopian adults. A simple random sampling of houses and a purposive sampling selection was performed in Mizan city, Ethiopia (n = 406). Participants completed the ISI and a meta-cognition questionnaire and sociodemographic information. IBM SPSS software with Amos was used for data analysis. There was no major ceiling or floor effect in the ISI scores. The internal consistency (Cronbach’s alpha = 0.68 and 0.78) and internal homogeneity (moderate to strong item-total ISI score correlations; r ≥ 0.47) were adequate. All of the ISI (item as well as total) scores correlated with the meta-cognition total scores (r = 0.16–0.44; p < .01). The exploratory factor analysis results were heterogeneous. However, the confirmatory factor analysis favored a 2-factor model. The ISI has good psychometric validity among Ethiopian adults with substance use.

Keywords:

• Alcohol
• Catha edulis
• khat
• sleep
• dependence

Acknowledgments

We thank the participants of the study as well as the Deanship of Scientific Research and RSSU at King Saud University for their technical support.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Ethics approval and consent to participate

The study was approved by the Human Institutional Ethics Committee of Mizan-Tepi University, and informed consent was obtained from all participants.

All authors have approved the final draft.

Clinical trials registry site and number

Not applicable.

Additional information

Funding

This work was supported by the Mizan-Tepi University faculty research fund. The funding body did not have any role in the design of the study, data collection, analysis, interpretation of the data, or the writing of the manuscript.