title: School environment as predictor of teacher sick leave: data-linked prospective cohort study.
abstract: BACKGROUND
  Poor indoor air quality (IAQ) and psychosocial problems are common in schools worldwide, yet longitudinal research on the issue is scarce. We examined whether the level of or a change in pupil-reported school environment (IAQ, school satisfaction, and bullying) predicts recorded sick leaves among teachers.
  
  
  METHODS
  Changes in the school environment were assessed using pupil surveys at two time points (2001/02 and 2004/05) in 92 secondary schools in Finland. Variables indicating change were based on median values at baseline. We linked these data to individual-level records of teachers' (n = 1678) sick leaves in 2001-02 and in 2004-05.
  
  
  RESULTS
  Multilevel multinomial logistic regression models adjusted for baseline sick leave and covariates showed a decreased risk for short-term (one to three days) sick leaves among teachers working in schools with good perceived IAQ at both times (OR = 0.6, 95% CI: 0.5-0.9), and for those with a positive change in IAQ (OR = 0.6, 95% CI: 0.4-0.9), compared to teachers in schools where IAQ was constantly poor. Negative changes in pupil school satisfaction (OR = 1.8, 95% CI: 1.1-2.8) and bullying (OR = 1.5, 95% CI: 1.0-2.3) increased the risk for short-term leaves among teachers when compared to teachers in schools where the level of satisfaction and bullying had remained stable. School environment factors were not associated with long-term sick leaves.
  
  
  CONCLUSIONS
  Good and improved IAQ are associated with decreased teacher absenteeism. While pupil-related psychosocial factors also contribute to sick leaves, no effect modification or mediation of psychosocial factors on the association between IAQ and sick leave was observed.
authors.affiliation: Finnish Institute of Occupational Health, Centre of Expertise for Work Organizations, Topeliuksenkatu 41 a A, 00250, Helsinki, Finland. jenni.ervasti@ttl.fi
authors.forename: Jenni
authors.initials: J
authors.lastname: Ervasti
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawachi
authors.forename: S V
authors.initials: SV
authors.lastname: Subramanian
authors.forename: Jaana
authors.initials: J
authors.lastname: Pentti
authors.forename: Tuula
authors.initials: T
authors.lastname: Oksanen
authors.forename: Riikka
authors.initials: R
authors.lastname: Puusniekka
authors.forename: Tiina
authors.initials: T
authors.lastname: Pohjonen
authors.forename: Jussi
authors.initials: J
authors.lastname: Vahtera
authors.forename: Marianna
authors.initials: M
authors.lastname: Virtanen
mesh_terms: D016902:Air Pollution, Indoor; D058445:Bullying; D016001:Confidence Intervals; D005178:Faculty / Q000706:statistics & numerical data; D005387:Finland; D005544:Forecasting; D006801:Humans; D016015:Logistic Models; D016017:Odds Ratio; D011446:Prospective Studies; D012574:Schools; D018582:Sick Leave / Q000706:statistics & numerical data / Q000639:trends*; D011795:Surveys and Questionnaires; D014691:Ventilation