Construct Validity and Clinical Utility of World Health Organization Disability Assessment Schedule 2.0 in Older Patients Discharged From Emergency Departments

Identifying the level of disability among older patients hospitalized with a medical diagnosis is an essential component of their treatment, as it is used to drive the discharge planning process and possible referral to rehabilitation (1). Discharge
planning often requires a multidisciplinary approach and involves a tailored plan for the patient to facilitate prompt and efficient discharge. Accordingly, instruments measuring different aspects of disability are used in a clinical context (2–4), including the Barthel Index, the Functional Independence Measure (FIM), the KATZ ADL Index, the 30-Second Chair Stand Test (30s-CST), and the Timed Up and Go (TUG) (2–4). The World Health Organization Disabilit Assessment Schedule 2.0 (WHODAS 2.0) (5) is based on the International
Classification of Functioning (ICF) framework (6). WHODAS 2.0 is a generic patient-reported instrument that measures functioning and disability. The use of WHODAS 2.0 is recommended as suitable for describing and quantifying the
level of disability associated with a health condition and is included in the new International Classification of Disease 11th revision (ICD-11) (7, 8). WHODAS 2.0 is a generic, multi-dimensional questionnaire that rates functioning from the
respondent’s subjective perspective. It enables comparison across different groups and settings for six different functional domains that reflect a hierarchy of disability, which is especially useful for clinical purposes and in research (5). There are different modes and versions of WHODAS 2.0, including 12- and 36-item versions, with the instrument having been translated into more
than 40 languages (5, 8–11). A number of studies have been conducted that examine the reliability and validity of the WHODAS 2.0 among different
populations (5, 9, 12–14). In a sample of 1,190 patients with chronic diseases, the 36-item interviewer-based version demonstrated high reliability and a good ability to discriminate and detect change over time (12). Additionally, the 36-item
version were found to have high reliability and validity in a sample of 1,000 elderly people (60–70 year) in Poland (10).In a systematic review of 810 studies, the authors concluded that WHODAS 2.0 offers a valid, reliable, self-report measure of disability for a variety of populations and settings (8). Although the psychometric properties of WHODAS 2.0 seem solid, the validity and clinical utility of WHODAS 2.0 among older patients with a medical diagnosis in an emergency department (ED) setting has not yet been explored. Accordingly,
the objective of this study was to examine the construct validity of WHODAS 2.0 and to describe its clinical utility for assessing disability and functioning among older patients discharged
from EDs.