Measurement invariance of the Facebook intrusion questionnaire across 25 countries.

Facebook is one of the most popular social networking sites. However, Facebook intrusion or addiction is a growing concern as it involves an excessive attachment to Facebook, which disrupts daily functioning. To date, few studies have examined whether cross-cultural differences in the measurement of Facebook addiction exist. The aim of this study was to investigate the cross-cultural validity and measurement invariance of the Facebook Intrusion Questionnaire (FIQ), one of the most widely used measures of Facebook addiction, across 25 countries (N = 12,204, 62.3% female; mean age = 25 years). Multigroup confirmatory factor analyses (MGCFA) assessed cross-cultural validity as well as invariance. Additionally, individual confirmatory factor analyses evaluated the factorial structure and measurement invariance across genders in each country. The FIQ demonstrated partial metric invariance across countries and metric (13 countries), scalar (11 countries) or residual (10 countries) invariance across genders within individual countries. A one-factor model indicated a good fit in 18 countries. Cronbach's alpha for the entire sample was .85. Our findings suggest that the FIQ may provide an adequate assessment of Facebook addiction that is psychometrically equivalent across cultures. Moreover, the questionnaire seems to be universal and suitable for studying different social media in distinct cultural environments. Consequently, this robust tool can be used to explore behaviours related to specific media that are particularly popular in any given country.

Circadian rhythm and sleep disruptions in relation to prenatal stress and depression symptoms.

Circadian rhythm and sleep are related to health, but there is little data on the relationship between the sleep/wake rhythm and mood at different stages of pregnancy. The aim of this prospective, longitudinal study was to investigate the associations of circadian rhythm and sleep disruptions with stress and depression among women in early and late pregnancy. The participants were 26 pregnant women. Objective and subjective estimations of circadian rhythm and sleep were administered, namely actigraphy and the Biological Rhythms Interview of Assessment in Neuropsychiatry in the form of a questionnaire. The Perceived Stress Scale and the Edinburgh Postnatal Depression Scale were also used. Subjectively perceived circadian rhythm disruptions were positively related to stress. Tendency to maintain a regular rhythm of sleep and activity in early pregnancy and subjectively perceived disruptions of circadian rhythms in late pregnancy were positively associated with prenatal depression in late pregnancy. Sleep fragmentation and long time spent in bed at night in early pregnancy were positively associated with stress and depression in late pregnancy. The results suggest the importance of flexibility and the ability to adapt one's circadian activities to the demands of the situation of pregnancy-related changes in lifestyle. They also indicate the significance of good-quality uninterrupted night sleep in early pregnancy.