WHODAS 2.0 ̵̵ 36 items
To evaluate the criterion validity of the Chinese version of the Scales,
we used the Chinese version of the WHODAS 2.0-36 items. A 5-point Likert
scale is used by participants to answer questions related to
difficulties performing activities. The score ranges from 0 (lowest
difficulty) to 100 (maximum difficulty) and is calculated as the sum of
each domain score.22 The higher the score is, the
higher the degree of disability and the more severe the restricted
situation. Restriction severity refers to the difficulty level
classification method of the ICF and WHODAS 2.0. The classification of
impairment severity is as follows: below 4% is none; 5-24% is mild;
25-49% is moderate; 50-95% is severe; and more than 96% is extremely
severe.23 In this study, only 32 items were calculated
because all the participants were retired and unemployed. Among the
reliability indices of the Chinese version of the WHODAS 2.0, Cronbach’sα for internal consistency is .70-.99, and the intra-class
correlation coefficient is .80-.89.24,25 Among the
validity indices, the content and the concurrent validity have some
correlation, and based on exploratory factor analyses (EFAs), 5-7
factors have an explanatory power higher than 55%. The factor loadings
of the CFA are all higher than .56.24 It has excellent
reliability and validity and is consistent with the item response theory
(IRT).