Analysis of the Psychometric Properties of the Glasgow Sleep Effort Scale Through Classical Test Theory, Item Response Theory, and Network Analysis

Purpose: The Glasgow Sleep Effort Scale was developed with the aim of measuring sleep effort. The present study evaluates the psychometric properties of the European Portuguese version of the scale through classical test theory (specifically confirmatory factor analysis), item response theory, and network analysis. Methods: It was used an existing database comprising a community sample of 227 Portuguese adults, aged 20–74 (M = 42.99; SD = 12.44) years old, comprising 49.8% women and 50.2% men. Results: In confirmatory factor analysis, a well-adjusted to data one-factor model was identified, with sleep effort as the single factor. Item response theory analysis indicated an adequate performance of all items and satisfactory coverage of the latent trait, with items 3 (a = 3.37), 4 (a = 3.18), and 6 (a = 3.02) as the most discriminative ones. Considering network analysis, items 4 and 7 presented the strongest edge weight (.48). Item 1 was displayed at the centre of the networks and accounted for the largest number of connections with the remaining items. Conclusion: The results suggest that the Glasgow Sleep Effort Scale is a reliable measure, comprising highly discriminative items with good centrality indices.