ERIC Number: EJ929065
Record Type: Journal
Publication Date: 2011-Jun
Abstractor: As Provided
Reference Count: 17
The Response Scale for the Intellectual Disability Module of the WHOQOL: 5-Point or 3-Point?
Fang, J.; Fleck, M. P.; Green, A.; McVilly, K.; Hao, Y.; Tan, W.; Fu, R.; Power, M.
Journal of Intellectual Disability Research, v55 n6 p537-549 Jun 2011
Objective: To deal with the question of whether a 5-point response Likert scale should be changed to a 3-point scale when used in the field testing of people with intellectual disabilities (IDs), which was raised after the pilot study of World Health Organization Quality of Life (WHOQOL)-DIS, a module being developed with the World Health Organization measure of quality of life for disabilities. Methods: Three possible ways were used to generate hypothetical data by merging a 5-point scale into a 3-point scale. The analyses were based on both item response theory and classical measurement theory. The partial credit model for polytomous response was performed for item evaluation; the confirmatory factor analysis was used to check construct validity, the Cronbach's alpha for domain reliability, and correlation analyses for the relationship between the 5-point scale and the generated 3-point scale. Results: Most items with a 5-point response scale had disordered response options and/or unequal-length intervals between successive response options; these deficiencies were removed or improved without decline of validity and reliability in the hypothetical data of 3-point scales. Conclusion: Instead of the 5-point scale, a 3-point scale could be used for IDs in the field test of developing the module WHOQOL-DIS.
Descriptors: Quality of Life, Likert Scales, Mental Retardation, Measures (Individuals), Item Response Theory, Factor Analysis, Correlation, Validity, Reliability
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Publication Type: Journal Articles; Reports - Evaluative
Education Level: N/A
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