Psychometric Validation and Evaluation of the Sleep Need Questionnaire

Background and Objective The Sleep Need Questionnaire (SNQ) is a widely used self-report measure used to detect self-perceived sleep need but has not yet been validated. Validation and reliability analyses were conducted on the SNQ in a sample of college students across multiple universities.Methods Total score and item-level convergent and discriminant validity were assessed utilizing various sleep and psychological measures. Construct validity and the structure of the SNQ were assessed using exploratory factor analysis (EFA) and item response theory via graded response modeling (GRM).Results The SNQ demonstrated moderate internal consistency (Cronbach’s α=0.74). Convergent analyses showed significant moderate to strong convergent correlations with other sleep-related constructs (r=0.46–0.74) and discriminant analyses showed mixed weak correlations with dissimilar constructs (r=0.04–0.10). The accuracy of the SNQ was examined through a receiver operating characteristic analysis with the Epworth Sleepiness Scale (ESS) as the criterion and indicated acceptable discrimination (area under the curve=0.73). EFA revealed a one-factor solution (λ=2.36) with a mixed range of significant inter-item correlations (r=0.165–0.833) and variable factor loadings (0.419–0.985). GRM revealed considerable imbalances in item functioning and potential redundancy.Conclusions Overall, the SNQ demonstrates moderate internal consistency and moderate to strong convergent and discriminant validity. Further analysis is needed to confirm and examine the unidimensional structure of the SNQ, as weak inter-item correlations, mixed factor loadings, and mixed item level behavior indicate structural and construct validity problems with the SNQ.