A short version of a HRQoL questionnaire for Italian and Japanese patients with Primary Biliary Cirrhosis☆
Abstract
Background
The available self-report questionnaire for the quality of life in patients with primary biliary cirrhosis (PBC-40) is currently validated only in the British population but it lacks an evaluation of its dimensionality.
Aims
To validate the Italian and Japanese versions of PBC-40 and to assess the dimensionality of the original structure of PBC-40 by a confirmatory factor analysis. PBC-40 was translated to Italian and Japanese using the forward–backward method and then reviewed in focus groups in the framework of a large multicentric study.
Methods
A sample of 290 patients with PBC (125 Italian and 165 Japanese) was administered two questionnaires previously validated for PBC-specific (PBC-40) and general quality of life (SF-36).
Results
The confirmatory model failed to fit adequately the original hypothesized structure. A principal component analysis led to a seven-factor structure, with exclusion of 13 items characterized by lower load; PBC-27 questionnaire was the final instrument. The validity of the PBC-27 was supported by its strong correlation with the SF-36 scores.
Conclusion
We here propose an alternative structure of the quality of life questionnaire for PBC, namely PBC-27, which appears to be effective in detecting the impact of PBC on quality of life in Italian and Japanese patients.
Abbreviations: PBC, primary biliary cirrhosis, HRQoL, health related quality of life, CFA, confirmatory factor analysis, CFI, comparative fit index, GFI, goodness of fit index, AGFI, adjusted goodness of fit index, RMSEA, root mean square error of approximation, CAIC, consistent Akaike's information criterion
Keywords: Factor structure, PBC-40, Principal component analysis, Quality of life
To access this article, please choose from the options below
☆ Grant support: Supported by Executive Program of Cooperation in the Field of Science and Technology between the Government of Italy and the Government of Japan.
PII: S1590-8658(10)00008-3
doi:10.1016/j.dld.2010.01.004
© 2010 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Inc All rights reserved.
