title: Child care is not a substantial risk factor for gastrointestinal infection hospitalization.
abstract: OBJECTIVE
  The objective was to study the effect of age at first enrollment into child care and other child care-related factors on the risk for hospitalization from gastrointestinal infection.
  
  
  METHODS
  This was a population-based prospective cohort study of 1,110,973 Danish children aged 0 to 5 years in the period 1989-2004. By means of Poisson regression, risk for gastrointestinal infection hospitalization was evaluated by incidence rate ratio and 95% confidence intervals.
  
  
  RESULTS
  Overall, children who were attending child care had an IRR of gastrointestinal infection hospitalization of 1.02 compared with children in home care. When compared within the group of children who attended child care, those who were enrolled after 18 months of age had a slightly increased risk compared with those who were enrolled before 1 year of age. The first 5 months of enrollment were associated with an IRR of 1.18 compared with later periods, and similar risks were observed in different types of child care facilities. The effect of child care was similar in most strata of the studied child, family, and demographic variables; however, children younger than 1 year who attended child care had an IRR of 1.44 compared with children of the same age in home care. Well established risk factors for gastrointestinal infection such as young age and male gender were reproduced; compared with 5-year-olds, children younger than 1 year had an IRR of 7.37 and boys had an IRR of 1.18 compared with girls.
  
  
  CONCLUSIONS
  The results of this study suggest that child care attendance is not a substantial risk factor for gastrointestinal infection hospitalization in most Danish children. Late enrollment and the first short period of enrollment were associated with a slightly increased risk for gastrointestinal infection hospitalization.
authors.affiliation: Statens Serum Institut, Department of Epidemiology Research, DK-2300 Copenhagen, Denmark. mka@ssi.dk
authors.forename: Mads
authors.initials: M
authors.lastname: Kamper-Jørgensen
authors.forename: Lise Geisler
authors.initials: LG
authors.lastname: Andersen
authors.forename: Jacob
authors.initials: J
authors.lastname: Simonsen
authors.forename: Signe
authors.initials: S
authors.lastname: Sørup
mesh_terms: D017677:Age Distribution; D002654:Child Care / Q000379:methods* / Q000706:statistics & numerical data; D002656:Child Day Care Centers / Q000706:statistics & numerical data*; D002675:Child, Preschool; D015331:Cohort Studies; D016001:Confidence Intervals; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005759:Gastroenteritis / Q000453:epidemiology* / Q000382:microbiology*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D016017:Odds Ratio; D016012:Poisson Distribution; D011446:Prospective Studies; D012042:Registries; D012307:Risk Factors; D017678:Sex Distribution