title: The LifeLines Cohort Study: a resource providing new opportunities for environmental epidemiology.
abstract: BACKGROUND
  Lifelines is a prospective population-based cohort study investigating the biological, behavioral and environmental determinants of healthy ageing among 167,729 participants from the North East region of the Netherlands. The collection and geocoding of (history of) home and work addresses allows linkage of individual-level health data to detailed exposure data. We describe the reasons for choosing particular assessments of environmental exposures in LifeLines and consider the implications for future investigations.
  
  
  METHODS
  Exposure to ambient air pollution and road traffic noise was estimated using harmonized models. Data on noise annoyance, perceived exposure to electromagnetic fields, perceived living environment, and neighborhood characteristics were collected with questionnaires. A comprehensive medical assessment and questionnaires were completed in order to assess determinants of health and well-being. Blood and urine samples were collected from all participants and genome wide association data are available for a subsample of 15,638 participants.
  
  
  RESULTS
  Mean age was 45 years (standard deviation (SD) 13 years), and 59 % were female. Median levels of NO2 and PM10 were 15.7 (interquartile range (IQR) 4.9) μg/m(3) and 24.0 (IQR 0.6) μg/m(3) respectively. Median levels of daytime road traffic noise were 54.0 (IQR 4.2) dB(A).
  
  
  CONCLUSIONS
  The combination of harmonized environmental exposures and extensive assessment of health outcomes in LifeLines offers great opportunities for environmental epidemiology. LifeLines aims to be a resource for the international scientific community.
authors.affiliation: Department of Epidemiology, University Medical Center Groningen, HPC CC72, University of Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands.
authors.forename: Wilma L
authors.initials: WL
authors.lastname: Zijlema
authors.affiliation: Department of Epidemiology, University Medical Center Groningen, HPC CC72, University of Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands.
authors.forename: Nynke
authors.initials: N
authors.lastname: Smidt
authors.affiliation: Department of Epidemiology, University Medical Center Groningen, HPC CC72, University of Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands.
authors.forename: Bart
authors.initials: B
authors.lastname: Klijs
authors.affiliation: Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, Imperial College London, London, UK.
authors.forename: David W
authors.initials: DW
authors.lastname: Morley
authors.affiliation: Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, Imperial College London, London, UK.
authors.forename: John
authors.initials: J
authors.lastname: Gulliver
authors.affiliation: Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, Imperial College London, London, UK ; Swiss Tropical and Public Health Institute, Basel, Switzerland ; University of Basel, Basel, Switzerland.
authors.forename: Kees
authors.initials: K
authors.lastname: de Hoogh
authors.affiliation: LifeLines Cohort Study, Groningen, The Netherlands.
authors.forename: Salome
authors.initials: S
authors.lastname: Scholtens
authors.affiliation: Department of Psychiatry, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Judith G M
authors.initials: JG
authors.lastname: Rosmalen
authors.affiliation: Department of Epidemiology, University Medical Center Groningen, HPC CC72, University of Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands ; LifeLines Cohort Study, Groningen, The Netherlands.
authors.forename: Ronald P
authors.initials: RP
authors.lastname: Stolk
keywords: Chronic disease; Prospective cohort study, Environmental exposures, Harmonization