Background: The assessment of disability in a population is an important part of public health management. In this article, we examine the psychometric properties and validation of the Polish version of the 12-item World Health Organization Disability Assessment Schedule 2.0. (12-item WHODAS 2.0).
Methods: A systematic random sample comprised 584 adult urban residents. The Polish version of the 12-item WHODAS 2.0 and the World Health Organization Quality of Life-BREF, Short Form (WHOQOL-BREF) questionnaire were used to assess disability and quality of life, respectively. Basic sociodemographic data and selected health-related data (e.g., pain and depressive moods) were also collected.
Results: Good scale score reliability for the entire tool was confirmed in the study population (Cronbach's α = 0.90; Composite reliability = 0.95). In confirmatory factor analysis (CFA), satisfactory values of the fit indices were obtained (comparative fit index, CFI = 0.999; Tucker-Lewis Index, TLI = 0.999; root mean square error of approximation, RMSEA = 0.004; standardized root mean square residual, SRMR = 0.043, p = 0.454). Good consistency was noted over time (correlation coefficient = 0.88). The tool was found to have an appropriate level of validity.
Conclusions: We found that the 12-item WHODAS is short and easy to use, and it is suitable for use in the form of an interview during screening tests. This tool is appropriate for measuring the health status, functioning, and disability of an average population. It may be more relevant for studying populations with health problems. The 12-item WHODAS can be used to successfully obtain information about the general level of disability in a population.