title: Validation of the Polish version of the World Health Organization Disability Assessment Schedule (WHODAS 2.0) in an elderly population (60-70 years old).
abstract: OBJECTIVE
  To assess the reliability and validity of the Polish version of the 36-point World Health Organization Disability Assessment Schedule (WHODAS 2.0) in an elderly population.
  
  
  METHODS
  One thousand randomly selected individuals, aged 60-70 years, living in south-eastern Poland were assessed using the Polish version of the WHODAS 2.0.
  
  
  RESULTS
  The analysis confirmed the high reliability and validity of the tool. Cronbach's α index was 0.89. The tool had high stability, and the correlation between test and retest results was high. The relevance of the domain selection was high or very high. A factor analysis confirmed the relevance of assigning questions to domains. High theoretical relevance was also demonstrated. Statistically significant differences between those who were and were not suffering from health problems were observed. An analysis of the internal structure of the WHODAS 2.0 revealed strong correlations between the components of each domain and the final result.
  
  
  CONCLUSIONS
  The Polish version of the WHODAS 2.0 showed high reliability and validity; thus, it can be used to assess health, functioning and disability in the elderly population of Poland.
authors.affiliation: a Institute of Physiotherapy, University of Rzeszow , Poland.
authors.forename: Agnieszka
authors.identifier: http://orcid.org/0000-0001-9958-6678
authors.initials: A
authors.lastname: Ćwirlej-Sozańska
authors.affiliation: a Institute of Physiotherapy, University of Rzeszow , Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Wilmowska-Pietruszyńska
authors.affiliation: b Centre for Innovative Research in Medical and Natural Sciences, University of Rzeszow , Poland.
authors.forename: Bernard
authors.initials: B
authors.lastname: Sozański
mesh_terms: D000368:Aged; D004185:Disability Evaluation; D006233:Persons with Disabilities; D006801:Humans; D008875:Middle Aged; D011044:Poland; D011788:Quality of Life; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards; D014944:World Health Organization
keywords: International Classification of Functioning, Disability and Health; WHODAS 2.0; disability identification; statistical analysis; translation