Validation of the Sleep Quality Questionnaire among senior students in Benin City, Nigeria.

Abstract

The Sleep Quality Questionnaire (SQQ) is a short and easy-to-understand resourceful tool for measuring poor sleep quality; however, it remains to be validated. The focus of this study is to determine its reliability and validity among Nigerian adolescents. Four gender-mixed schools within Benin City, Nigeria were selected to participate in the study. Questionnaires containing the SQQ, the Sleep Condition Indicator (SCI), which is a validated scale, and the Hospital Anxiety and Depression Scale (HADS) from 377 students selected from the junior and senior secondary school students were analysed. The mean age calculated was 14.78 years for 174 male and 203 female students. Cronbach's alpha for the SQQ scale was 0.70. It correlated strongly with the SCI (rho = 0.93, p = 0.00), weakly with the HADS depression (rho = -0.19, p < 0.01) and anxiety (rho = -0.30, p < 0.01), but had no association with gender. Factor analysis revealed three factors with an eigenvalue greater than 1. Factors 1-3 accounted for 31.78%, 15.16% and 11.26% of the variance, respectively, totalling 58.2%. The reliability of each of the three factors was as follows: factor 1, 0.75; factor 2, 0.47; and factor 3, 0.62. The SQQ demonstrated good specificity and sensitivity at a cut-off point of 18. It is therefore recommended that the SQQ be included in the screening of sleep-related problems in adolescents, both in the primary and secondary care settings in Nigeria. The research shows that the Sleep Quality Questionnaire is both a reliable and valid screening tool among adolescents in Nigeria. Its brevity and simplicity further promote its use in clinical and non-clinical settings.