A Systematic Review of Instruments for the Assessment of Insomnia in Adults

Introduction: Self-reported sleep instruments remain the most practical methods for the assessment of insomnia in clinical practice. This systematic review aims to identify, describe and summarize the psychometric properties of questionnaires available for the assessment of insomnia in the adult population. In addition, the review also aimed to identify sleep instruments available in the Arabic language. Methods: A systematic literature search was conducted using the following electronic databases: PubMed, EMBASE, ProQuest Central, SCOPUS, and Google Scholar. The quality assessment of the instruments was conducted using two established international criteria. Results: One hundred and seven articles were selected for inclusion, from which 31 instruments were identified and categorized based on the constructs they assess as: (1) screening for insomnia (n=14); (2) measuring the consequences of insomnia (n=8); (3) assessing the cognitive aspects of insomnia (n= 5); and (4) assessing sleep hygiene (n= 4). The review of the psychometric properties showed that the Insomnia Severity Index and the Functional Outcomes of Sleep Questionnaire were the most extensively evaluated instrument. Criterion validity and reliability measures were the most commonly reported properties. Only four of the identified instruments were available in Arabic. Discussion: Overall, the findings of this study indicate ample availability of sleep instruments. However, psychometric testing for several of the available sleep instruments remains incomplete, particularly responsiveness and interpretability. Our findings suggest that future studies should focus on reporting more psychometric measures to ensure the trustworthiness of these instruments.