Development and initial testing of a brief, generic self-reported disability questionnaire: The Universal Disability...

Area of Science:

• Health Sciences
• Psychometrics
• Disability Studies

Background:

• Disability is a complex, multifaceted construct.
• Existing disease-specific instruments limit broad disability measurement.
• A need exists for a brief, generic self-reported disability questionnaire.

Purpose of the Study:

• To develop and evaluate the Universal Disability Index (UDI) questionnaire.
• To create a tool for broader and more comparable disability measurement.
• To assess the psychometric properties of the UDI.

Main Methods:

• Online survey data collected from the general population.
• Exploratory and confirmatory factor analysis (EFA & CFA) used for UDI structure evaluation.
• Concurrent validity assessed against established disability scales (GARS, GCPS).

Main Results:

• Three UDI versions (8, 7, and 6 items) showed good performance in EFA and CFA.
• All UDI versions demonstrated high internal consistency (Cronbach's α > 0.90).
• Strong correlations with GARS and GCPS confirmed concurrent validity.

Conclusions:

• A brief, generic self-reported disability questionnaire (UDI) is valid and has good psychometric properties.
• The UDI exhibits a single-factor structure.
• The 6-item UDI is recommended for brevity, with further testing encouraged.