RESUMO
Insufficient sleep could severely impair both cognitive and learning skills. More prominent changes are found in children and adolescents. Tools used to estimate sleepiness in the adult population are commonly inappropriate for children. The objective of our study was to provide a reliable instrument to measure excessive sleepiness for upcoming studies in Russian-speaking children, applying the Russian version of Pediatric Daytime Sleepiness Scale (PDSS). The following tasks were resolved in our study: translation, validation, and analysis of psychometric properties of the Russian adaptation of the PDSS by standard tests. After the semantic validation of the instrument through a multi-stage translation process we checked its psychometric validation. A total of 552 students, consisting of N = 285 for the exploratory factor analysis (EFA), N = 267 for the confirmatory factor analysis (CFA) and N = 204 for test-retest analysis of public elementary schools located in Northern Russia completed the PDSS and Munich Chronotype Questionnaire to estimate sleep parameters in the classroom during the lessons. Response rate was 90%; excluded cases contained no data. Further, 204 of our participants completed the PDSS in a 3 months interval to check the test-retest reliability. Internal consistency was measured by Cronbach's alpha coefficients and CFA was used to test factorial validity of the tool. Concurrent validity and test-retest reliability were assessed via intra-class coefficient. Internal consistency of the PDSS scale was high (Cronbach's α = 0.8). The construct validity of the PDSS was supported by CFA (factor loadings were from 0.438 to 0.727) and the test-retest reliability demonstrated by the intra-class coefficient was 0.70. The total PDSS score was independent of sex. The mean total value of PDSS was 11.95 ± 6.24. Higher scores on PDSS were negatively correlated with sleep duration. Thus, the construct validity of the instrument remains valid and could be used for Russian-speaking youth samples in the evaluation of daytime sleepiness. It could be useful in future applications by sleep scientists and health practitioners.
RESUMO
Complex investigation of solar, geophysical and meteorological factors as well as lunar cycle-phases effects on the indices of cardiohemodynamics, emotional state and the CNS functional state was carried out in 12 males 19-38 years old living in the Arctic region (Apatity, 67°57' N, 33°39' E). The observation period was characterized by flares of M1-M2-class as well as geomagnetic storms of G1-G3 class. Adaptive modulatory effect of environmental factors was shown on the autonomic regulatory systems, as well as a strongviolation action of geomagnetic storms and solar chromosphere flares were revealed on the human functional state. Multiple regression method allowed us to obtain the dominant environmental factors by magnitude of their action on functional parameters, and to estimate the combined effect of these factors. The coefficient of determination in the most cases did not exceed 0.5, but in a certain subjects reached 0.7-0.8 on some indicators. Data show the selective nature of the multiple effects of environmental factors on indicators of functional and emotional states at various persons. Each of examined subjects living in the high latitude extreme conditions reacts on permanent climatic-geographic and cosmophysical factors variation, however both a character and magnitude of reactions were dependent on personal susceptibility to isolated and combined actions of these factors.