Psychometric evaluation of the 12-item WHODAS 2.0 in trauma-affected refugees with PTSD

Background

Trauma-affected refugees often experience impaired functioning due to psychiatric symptoms and post-migration stressors. The World Health Organization Disability Assessment Schedule (WHODAS 2.0) is increasingly used in refugee mental health research, but its measurement properties in clinical refugee populations have not been sufficiently examined. This study evaluated the psychometric properties of the clinician-rated 12-item WHODAS in trauma-affected refugees with PTSD.

Methods

Baseline data were combined from two randomized controlled trials (N = 214) conducted at a specialized outpatient clinic for trauma-affected refugees in Denmark. Participants were adult refugees diagnosed with PTSD. Rasch analysis examined model fit, dimensionality, reliability, and differential item functioning across key subgroups.

Results

The baseline model showed acceptable global fit (p = .060), but evidence of multidimensionality, item misfit, and differential item functioning. Items related to mobility and self-care formed a distinct somatic subdimension separate from the remaining psychosocial items. A modified seven-item psychosocial subscale showed acceptable fit after accounting for local dependence and differential item functioning by sex and education. These findings indicate that different aspects of functioning are captured across items rather than a single construct. Men reported greater concentration difficulties, and respondents with lower education reported greater difficulties learning new tasks at the same trait level.

Conclusions

The 12-item WHODAS captures important aspects of functioning in trauma-affected refugees with PTSD, but it may not function as a strictly unidimensional measure. Total scores should therefore be interpreted with caution. Item-level responses may provide clinically useful information about functional profiles and barriers to recovery, particularly when functioning is shaped by both psychiatric symptoms and post-migration stressors.

Key messages

• WHODAS-12 captures functioning in trauma-affected refugees but is not strictly unidimensional; total scores should be interpreted with caution.

• Item-level responses can identify functional profiles and barriers to recovery, supporting more targeted and patient-centred interventions.