title: Association of sleep duration with socio-economic status and behavioural problems among schoolchildren.
abstract: OBJECTIVE
  In this population-based study, we aimed to determine the total sleep duration (TSD), its association with socio-economic status (SES) and behavioural symptoms among schoolchildren.
  
  
  METHODS
  A cross-sectional study was performed among schoolchildren in Istanbul. A structured questionnaire evaluating the sleep schedule variables was filled out by their parents. SES was determined according to the Turkish SES scale.
  
  
  RESULTS
  The mean age of 2669 children was 8.2 ± 2.4 years, and 51% of the students were girls. The mean TSD was 10.20 ± 1.04, and the mean bedtime was 21.57 ± 0.56 (both in hours, minutes ± SD). Boys tended to go bed later (p = 0.004) and slept less than girls (p = 0.02). The duration of sleep disruptions increased (p < 0.001), whereas TSD decreased with age (p < 0.001). Multiple linear regression revealed that waking time and TSD decreased significantly (p < 0.05) with higher SES among both girls and boys. Sleep fragmentation was associated with habitual snoring, parasomnias, daytime sleepiness and conduct symptoms.
  
  
  CONCLUSIONS
  Decreased total sleep duration is more prominent in boys, older children and children among higher socio-economic status. Insufficient sleep attributed to shortened total sleep duration by age and higher socio-economic status might have a negative effect on both sleep hygiene and psychological well-being in schoolchildren.
authors.affiliation: Department of Child and Adolescent Psychiatry, Marmara University Hospital, Istanbul, Turkey. aarman@marmara.edu.tr
authors.forename: Ayse Rodopman
authors.initials: AR
authors.lastname: Arman
authors.forename: Pinar
authors.initials: P
authors.lastname: Ay
authors.forename: Nese Perdahli
authors.initials: NP
authors.lastname: Fis
authors.forename: Refika
authors.initials: R
authors.lastname: Ersu
authors.forename: Ahmet
authors.initials: A
authors.lastname: Topuzoglu
authors.forename: Ugur
authors.initials: U
authors.lastname: Isik
authors.forename: Meral
authors.initials: M
authors.lastname: Berkem
mesh_terms: D002648:Child; D002653:Child Behavior Disorders / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D012307:Risk Factors; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000453:epidemiology*; D012923:Social Class; D011795:Surveys and Questionnaires; D013997:Time Factors; D014421:Turkey / Q000453:epidemiology