title: Which environmental factors are associated with lived health when controlling for biological health? - a multilevel analysis.
abstract: BACKGROUND
  Lived health and biological health are two different perspectives of health introduced by the International Classification of Functioning, Disability and Health (ICF). Since in the concept of lived health the impact of the environment on biological health is inherently included, it seems intuitive that when identifying the environmental determinants of health, lived health is the appropriate outcome. The Multilevel Item Response Theory (MLIRT) model has proven to be a successful method when dealing with the relation between a latent variable and observed variables. The objective of this study was to identify environmental factors associated with lived health when controlling for biological health by using the MLIRT framework.
  
  
  METHODS
  We performed a psychometric study using cross-sectional data from the Spanish Survey on Disability, Independence and Dependency Situation. Data were collected from 17,303 adults living in 15,263 dwellings. The MLIRT model was used for each of the two steps of the analysis to: (1) calculate people's biological health abilities and (2) estimate the association between lived health and environmental factors when controlling for biological health. The hierarchical structure of individuals in dwellings was considered in both models.
  
  
  RESULTS
  Social support, being able to maintain one's job, the extent to which one's health needs are addressed and being discriminated against due to one's health problems were the environmental factors identified as associated with lived health. Biological health also had a strong positive association with lived health.
  
  
  CONCLUSIONS
  This study identified environmental factors associated with people's lived health differences within and between dwellings according to the MLIRT-model approach. This study paves the way for the future implementation of the MLIRT model when analysing ICF-based data.
authors.affiliation: Department of Health Sciences and Health Policy, University of Lucerne, Lucerne, Switzerland. cristina.bostan@paraplegie.ch.|Swiss Paraplegic Research, Nottwil, Switzerland. cristina.bostan@paraplegie.ch.
authors.forename: Cristina
authors.initials: C
authors.lastname: Bostan
authors.affiliation: Department of Medical Informatics, Biometry and Epidemiology-IBE, Pettenkofer School of Public Health (PSPHLMU), Research Unit for Biopsychosocial Health, Ludwig Maximilian University (LMU), Munich, Germany. cornelia.oberhauser@med.uni-muenchen.de.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Oberhauser
authors.affiliation: Department of Health Sciences and Health Policy, University of Lucerne, Lucerne, Switzerland. gerold.stucki@paraplegie.ch.|Swiss Paraplegic Research, Nottwil, Switzerland. gerold.stucki@paraplegie.ch.
authors.forename: Gerold
authors.initials: G
authors.lastname: Stucki
authors.affiliation: Department of Health Sciences and Health Policy, University of Lucerne, Lucerne, Switzerland. jerome.bickenbach@paraplegie.ch.|Swiss Paraplegic Research, Nottwil, Switzerland. jerome.bickenbach@paraplegie.ch.
authors.forename: Jerome
authors.initials: J
authors.lastname: Bickenbach
authors.affiliation: Swiss Paraplegic Research, Nottwil, Switzerland. a.cieza@soton.ac.uk.|Department of Medical Informatics, Biometry and Epidemiology-IBE, Pettenkofer School of Public Health (PSPHLMU), Research Unit for Biopsychosocial Health, Ludwig Maximilian University (LMU), Munich, Germany. a.cieza@soton.ac.uk.|Faculty of Social and Human Sciences, School of Psychology, University of Southampton, Southampton, UK. a.cieza@soton.ac.uk.
authors.forename: Alarcos
authors.initials: A
authors.lastname: Cieza
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D006233:Persons with Disabilities / Q000523:psychology* / Q000706:statistics & numerical data*; D004651:Employment / Q000523:psychology; D004777:Environment; D005260:Female; D006304:Health Status; D006801:Humans; D064702:International Classification of Functioning, Disability and Health; D008297:Male; D008875:Middle Aged; D055361:Multilevel Analysis; D011594:Psychometrics; D012111:Residence Characteristics; D012944:Social Support; D013030:Spain; D011795:Surveys and Questionnaires