RESUMEN
AIM: The Pittsburgh Sleep Quality Index is a widely used measure of sleep quality. The validity and reliability of the Danish version of the instrument has not yet been established. The aim of this study is to establish the internal consistency, test-retest reliability and convergent validity of the Danish version of the Pittsburgh Sleep Quality Index in adolescents. METHODS: Data were collected from 719 students from 17 different upper secondary schools. The sample consisted of 55% women, and the mean age of the sample was 17.87 (2.52) years. Data was collected on two occasions approximately 6 weeks apart using online surveys. Apart from the Pittsburgh Sleep Quality Index, the students also completed the five-item World Health Organization Well-being Index and the 10-item Perceived Stress Scale. For internal consistency the Cronbach's alpha was calculated, for test-retest reliability the interclass correlation coefficient was computed, and for validity the Pearson's correlation was calculated. RESULTS: The mean global Pittsburgh Sleep Quality Index score among Danish adolescents was 5.86 (3.13). The internal consistency for the Pittsburgh Sleep Quality Index was satisfactory with a Cronbach's alpha of 0.72. Test-retest reliability was adequate with an interclass correlation coefficient of 0.68. Finally, the Pittsburgh Sleep Quality Index showed large positive correlation with the 10-item Perceived Stress Scale (0.55) and a large negative correlation with the five-item World Health Organization Well-being Index (-0.59). CONCLUSIONS: The Danish version of the Pittsburgh Sleep Quality Index showed adequate reliability and validity among Danish adolescents.
Asunto(s)
Calidad del Sueño , Sueño , Adolescente , Humanos , Femenino , Masculino , Reproducibilidad de los Resultados , Psicometría , Encuestas y Cuestionarios , DinamarcaRESUMEN
In working memory training studies, individual trajectories are known to vary considerably between participants. A better understanding of how individual differences affect training outcomes is important because it might inform the development of more effective training interventions. This study explored how measures of working memory, intelligence, sustained attention, training motivation, mindset, psychological well-being, perceived stress, and sleep quality affect initial training performance and rate of change. A total of 217 upper secondary students completed 12 weeks of adaptive dual-n-back in a classroom setting. We analyzed their self-reported training data using latent growth curve modeling. We found that working memory and intelligence predicted both, initial training performance and rate of performance change. Sustained attention and sleep quality predicted initial performance, but not the rate of change. Furthermore, we observed that participants who completed the intervention scored significantly higher on measures of working memory and intelligence and reported lower levels of perceived stress and higher levels of sleep quality at baseline compared to dropouts. In general, our study supports the magnification account with higher ability individuals starting out at a higher performance level and showing a higher rate of performance change, and moreover, being more likely to adhere to the training protocol.