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Gepubliceerd in: Quality of Life Research 4/2013

01-05-2013

A new look at the WHOQOL as health-related quality of life instrument among visually impaired people using Rasch analysis

Auteurs: Vijaya K. Gothwal, Marmamula Srinivas, Gullapalli N. Rao

Gepubliceerd in: Quality of Life Research | Uitgave 4/2013

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Abstract

Purpose

To examine the psychometric characteristics of the World Health Organization Quality of Life instrument—modified Indian version (modified WHOQOL) and its subscales in adults with visual impairment (VI) using Rasch analysis.

Methods

Cross-sectional data were of people aged ≥40 years with VI (n = 1,333) who responded to the modified WHOQOL in the Andhra Pradesh Eye Disease Study, India. Rasch analysis was used to explore the instrument and its subscales for key indices such as measurement precision by person separation reliability, PSR (i.e., discrimination between strata of participants’ health-related QOL [HRQOL], recommended minimum value 0.8), unidimensionality (i.e., measurement of a single construct), and targeting (i.e., matching of item difficulty to participants’ HRQOL).

Results

Rasch-guided iterative approach including category re-organization to enable threshold ordering and item deletion to overcome multidimensionality resulted in a unidimensional 9-item WHOQOL and a 6-item level of independence (LOI) subscale with adequate PSR (0.81 and 0.82, respectively). Targeting was sub-optimal for both (−1.58 logits for WHOQOL and −2.55 logits for the subscale). Remaining subscales were dysfunctional.

Conclusions

The WHOQOL and LOI subscale can be improved and shortened, and the Rasch-revised versions are likely to assess the HROQL of VI patients best because of their brevity, reliability, and unidimensionality.
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Metagegevens
Titel
A new look at the WHOQOL as health-related quality of life instrument among visually impaired people using Rasch analysis
Auteurs
Vijaya K. Gothwal
Marmamula Srinivas
Gullapalli N. Rao
Publicatiedatum
01-05-2013
Uitgeverij
Springer Netherlands
Gepubliceerd in
Quality of Life Research / Uitgave 4/2013
Print ISSN: 0962-9343
Elektronisch ISSN: 1573-2649
DOI
https://doi.org/10.1007/s11136-012-0195-6

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