The European Portuguese version of the insomnia severity index.

Insomnia is the most prevalent sleep complaint, but remains largely an unidentified public health issue. The Insomnia Severity Index (ISI) is a brief self-report questionnaire to assess insomnia, long-established both in clinical and research settings. The present study aimed to analyse the reliability, validity, and accuracy of the ISI European Portuguese version.

An epidemiological study of sleep-wake timings in school children from 4 to 11 years old: insights on the sleep phase shift and implications for the school starting times' debate.

Objective: It has been assumed that during adolescence there is a strong shift toward eveningness chronotype, whereas children's sleep is relatively stable. Several studies have focused on the conflict between school start times and adolescents' circadian rhythms; however, fewer studies have been conducted in younger children. The aim of this study was to examine sleep durations, schedules, and sleep phase shift in preschool- and school-aged children.