Differences in disability detection between ICF tools: WHODAS 2.0 vs. ICF checklist

Objective: To examine the psychometric properties of the World Health Organization Disability Assessment Schedule (WHODAS 2.0) and the International Classification of Functioning, Disability and Health Checklist (ICF Checklist) for measuring functioning in a general population aged 50 and older in the Autonomous Community of Aragon (Spain).

Methods: A quantitative cross-sectional study was conducted in a community setting (both rural and urban areas) involving 1,707 participants. Disability was assessed using the 12-item WHODAS 2.0, the 36-item WHODAS 2.0, and the World Health Organization ICF Checklist.

Results: The detection of none/mild disability was significantly higher using the ICF Checklist (90.7%) compared to the 12-item WHODAS (62.0%) and the 36-item WHODAS (70.5%). Conversely, moderate/severe disability was significantly higher (p < 0.001) in both the 12-item (38.0%) and 36-item WHODAS (28.5%) than in the ICF Checklist (9.3%). Both versions of WHODAS 2.0 demonstrated higher sensitivity (88.5% and 97.4%, respectively) than specificity (58.8%), showing little variation across domains. Additionally, 10.9% of participants screened positive on the Mini-Mental State Examination (MMSE).

Conclusions: WHODAS 2.0 is a sensitive tool for disability screening; However, its low specificity may lead to an overestimation of prevalence compared to the ICF Checklist. Therefore, combining both tools in research and clinical practice is recommended to achieve a comprehensive assessment of disability.