title: Children's television exposure and behavioral and social outcomes at 5.5 years: does timing of exposure matter?
abstract: BACKGROUND
  The American Academy of Pediatrics recommends children > or = 2 years of age limit daily media exposure to < or = 1 to 2 hours and not have a television set in children's bedrooms. However, there are limited prospective studies to address how timing of media exposure influences children's health.
  
  
  OBJECTIVE
  Our goal was to examine relations among children's early, concurrent, and sustained television exposure and behavioral and social skills outcomes at 5.5 years.
  
  
  METHODS
  We analyzed data collected prospectively from the Healthy Steps for Young Children national evaluation. Television exposure was defined as > 2 hours of daily use (at 30-33 months and 5.5 years) and television in child's bedroom (at 5.5 years). At 5.5 years, outcomes were assessed by using the Child Behavior Checklist and social skills using the Social Skills Rating System. Linear regression was used to estimate the effect of television exposure on behavioral and social skills outcomes.
  
  
  RESULTS
  Sixteen percent of parents reported that their child watched > 2 hours of television daily at 30 to 33 months only, 15% reported > 2 hours of television daily at 5.5 years only, and 20% reported > 2 hours of television daily at both times. Forty-one percent of the children had televisions in their bedrooms at 5.5 years. In adjusted analyses, sustained television viewing was associated with behavioral outcomes. Concurrent television exposure was associated with fewer social skills. For children with heavy television viewing only in early childhood, there was no consistent relation with behavioral or social skills outcomes. Having a television in the bedroom was associated with sleep problems and less emotional reactivity at 5.5 years but was not associated with social skills.
  
  
  CONCLUSIONS
  Sustained exposure is a risk factor for behavioral problems, whereas early exposure that is subsequently reduced presents no additional risk. For social skills, concurrent exposure was more important than sustained or early exposure. Considering the timing of media exposure is vital for understanding the consequences of early experiences and informing prevention strategies.
authors.affiliation: Department of Population, Family, and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA. kmistry@jhsph.edu
authors.forename: Kamila B
authors.initials: KB
authors.lastname: Mistry
authors.forename: Cynthia S
authors.initials: CS
authors.lastname: Minkovitz
authors.forename: Donna M
authors.initials: DM
authors.lastname: Strobino
authors.forename: Dina L G
authors.initials: DL
authors.lastname: Borzekowski
mesh_terms: D000342:Affective Symptoms / Q000453:epidemiology; D002653:Child Behavior Disorders / Q000453:epidemiology*; D002675:Child, Preschool; D005500:Follow-Up Studies; D006801:Humans; D007398:Interpersonal Relations; D015999:Multivariate Analysis; D011446:Prospective Studies; D012893:Sleep Wake Disorders / Q000453:epidemiology; D013690:Television; D013997:Time Factors