Structural and Construct Validity of the WHO Disability Assessment Schedule (WHO-DAS 2.0) on the Population of Slovenian Patients with Depression and Normative Controls

Povzetek

The study investigates the structural and construct validity of the World Health Organization Disability
Assessment Schedule (WHO-DAS 2.0) within a Slovenian population comprising patients with depression
and normative controls. WHO-DAS 2.0, a widely used instrument for assessing functional disability
across seven domains, was translated into Slovene and validated using a range of statistical analyses,
including exploratory and confirmatory factor analysis, internal consistency measures, and construct
validity tests. Results indicated significant differences in functional disability between patient and
normative groups, with patients reporting higher levels of impairment. Factor analysis revealed that
the Slovene translation deviates from the nominal seven-domain structure, suggesting a one-factor
model after excluding cognitive dysfunction items due to low construct validity. The study also de-
monstrated strong internal consistency (Cronbach’s alpha = 0.940) and significant correlations with
related construct (depression, anxiety, and depression-related functional disability). These findings
support the use of WHO-DAS 2.0 as a reliable tool for assessing functional disability in Slovenian cli-
nical and normative populations.