Factor structure and psychometric properties of the Persian versions of the Pediatric Daytime Sleepiness Scale and Morningness-Eveningness Scale for Children

Persian version of brief infant sleep questionnaire (BISQ): a psychometric evaluation

BACKGROUND

The high prevalence of sleep problems and their negative consequences on children and parents highlight the need to design early screening instruments to evaluate sleep problems in early childhood. We aimed to determine the validity and reliability of the Brief Infant Sleep Questionnaire (BISQ) among the Iranian population.

METHODS AND MATERIALS

This study included 646 one-year-old infants by random sampling from the PERSIAN birth cohort study. Following the forward-backward translation of the BISQ, its psychometric properties, including construct validity in terms of concurrent and convergent validities as well as reliability, were evaluated.

RESULTS

The CVIs and CVR ranged between 0.8 and 1.00 for all items. Therefore, we keep all the items of the original version of the BISQ in the Persian BISQ. Concurrent validity was assessed by comparing items of the Persian BISQ among different maternal views regarding their infant's sleep. All BISQ items were significantly different among the two levels of maternal view about the infant's sleep problem except daytime sleep duration. The convergent validity of the BISQ was evaluated by calculating the correlation between BISQ items and the ISQ (infant sleep questionnaire) total score as a similar tool. ISQ score was adequately correlated with nocturnal sleep latency and the number of waking at night (rs ranged from 0.59 to 0.72). In addition, the associations of mothers' and infants' demographic variables and nutritional and gestational variables with BISQ items were presented to confirm construct validity. Strong correlations were found between the repeated sleep measures for sleep arrangement, sleep position, and sleep situation (kappa ranged from 0.65 to 0.84), nocturnal sleep duration, daytime sleep duration number of wakings at night, night waking duration, nocturnal sleep latency and sleep-onset time (ICC ranged 0.91 to 0.99).

CONCLUSION

The Persian version of the BISQ is a reliable and valid measure for assessing sleep problems in infants. It would be helpful to be utilized for the early diagnosis of infants' sleep problems.

Factors that influence morningness-eveningness and daytime sleepiness: A cross-cultural comparison of Iranian and Brazilian adolescents

As adolescents get older, they become more evening oriented and, because they are usually expected to wake early to attend school, they often present daytime sleepiness, which is associated with negative outcomes. It is still unclear if this is similar cross-culturally. Here, we studied morningness-eveningness and daytime sleepiness in early adolescence from two different developing nations (Brazil and Iran). A total sample of 697 Iranian and Brazilian early adolescents (9- to 15-year-old; 358 boys) from Tehran, Iran, and São Paulo, Brazil, varying in age and parental schooling (a proxy of socioeconomic status: SES) completed the Morningness-Eveningness Scale for Children (MESC) and the Pediatric Daytime Sleepiness Scale (PDSS) and reported their total sleep time on school nights. They also filled in the Pubertal Developmental Scale to determine their pubertal status. A negligible cross-cultural difference in morningness-eveningness was found, indicating that Brazilians showed a slight circadian-phase delay compared with Iranians throughout all tested ages. There was also seen a very slight increase in phase delay as early adolescents aged, indicative of more eveningness. However, there were no country differences in daytime sleepiness once total sleep time during school nights was controlled for, which was the only factor that affects PDSS scores.

Fractionation of executive functions in adolescents from Iran: invariance across age and socioeconomic status

Executive functions (EFs) are cognitive skills that regulate thoughts and behavior. The seminal EF unity and diversity theoretical framework proposes the existence of three correlated EF latent domains (inhibition, updating, and switching) that become distinguishable from a certain moment during adolescence, but it is unclear how age and socioeconomic status (SES) affect these abilities. Here, we assessed 407 9-15-year-old Iranians of variable SES using an open-access battery of executive function tests that includes two tasks of each EF domain and allows for sociocultural adaptations regarding language and stimuli. Various EF model configurations proposed in the literature were tested (one, two and three EF latent factor, nested and bifactor-S-1 models) using confirmatory factor analyses. In addition, to explore the unbiased effects of age and SES, we performed invariance testing (across age and SES) using multiple indicators multiple causes (MIMIC) model to the best fitting model solution. The three-correlated EF factor model had the best fit and was mostly invariant across age and SES, with all three EF latent traits improving with age, while SES exerted only minimal positive effects on shifting and updating. We concluded that the three separable EF domains, found in adults and adolescents of other ages from different populations, can already be detected from the beginning of adolescence when culturally and psychometrically appropriate EF tasks are used. Additionally, these abilities continue to improve with age and are little affected by SES, suggesting that the unity and diversity framework is useful to study the cross-country generality of EF development.