We have located links that may give you full text access.
Comparative Study
Journal Article
Factor structure of the Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire evaluated in patients with heartburn predominant reflux disease.
Quality of Life Research 2003 September
AIM: To test whether the original factor structure of the Quality of Life in Reflux and Dyspepsia (QOLRAD) can be replicated in Nordic patients and English speaking patients.
PATIENTS AND METHODS: Clinical trial patients with heartburn without esophagitis completed the Swedish, Norwegian, Finnish and Danish versions (n = 634) and the English version (n = 1185). The factor structure was examined using models generated by exploratory and confirmatory factor analysis.
RESULTS: The exploratory factor analysis suggested that the original five-factor structure solution was the most optimal. The Nordic versions explained 67% and the English version 72% of the variance. The factor loading of 22 out of 25 items was >0.55. In the confirmatory factor analysis, because of the sample size, only the Swedish and Norwegian data were used. Confirmatory factor analysis indicated an acceptable goodness of fit of the five-factor solution to the data with a goodness of fit index of 0.85 in the Swedish, 0.77 in the Norwegian and 0.91 in the English speaking population. The internal consistency reliability ranged from 0.70 to 0.94 (in the Nordic translations) and from 0.85 to 0.92 (in the English version), supporting the homogeneity of the items within the factors and thus their construct validity. The QOLRAD distinguished severity and frequency of heartburn, thereby documenting its known-group validity to distinguish between groups of patients.
CONCLUSIONS: The factor structure and dimensionality of the English version and the Swedish and Norwegian translations of the QOLRAD could be replicated by the exploratory and confirmed by the confirmatory factor analysis. The QOLRAD is a valid and reliable instrument for use in clinical trials.
PATIENTS AND METHODS: Clinical trial patients with heartburn without esophagitis completed the Swedish, Norwegian, Finnish and Danish versions (n = 634) and the English version (n = 1185). The factor structure was examined using models generated by exploratory and confirmatory factor analysis.
RESULTS: The exploratory factor analysis suggested that the original five-factor structure solution was the most optimal. The Nordic versions explained 67% and the English version 72% of the variance. The factor loading of 22 out of 25 items was >0.55. In the confirmatory factor analysis, because of the sample size, only the Swedish and Norwegian data were used. Confirmatory factor analysis indicated an acceptable goodness of fit of the five-factor solution to the data with a goodness of fit index of 0.85 in the Swedish, 0.77 in the Norwegian and 0.91 in the English speaking population. The internal consistency reliability ranged from 0.70 to 0.94 (in the Nordic translations) and from 0.85 to 0.92 (in the English version), supporting the homogeneity of the items within the factors and thus their construct validity. The QOLRAD distinguished severity and frequency of heartburn, thereby documenting its known-group validity to distinguish between groups of patients.
CONCLUSIONS: The factor structure and dimensionality of the English version and the Swedish and Norwegian translations of the QOLRAD could be replicated by the exploratory and confirmed by the confirmatory factor analysis. The QOLRAD is a valid and reliable instrument for use in clinical trials.
Full text links
Related Resources
Trending Papers
Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies.Journal of Personalized Medicine 2024 Februrary 4
Molecular Targets of Novel Therapeutics for Diabetic Kidney Disease: A New Era of Nephroprotection.International Journal of Molecular Sciences 2024 April 4
The 'Ten Commandments' for the 2023 European Society of Cardiology guidelines for the management of endocarditis.European Heart Journal 2024 April 18
A Guide to the Use of Vasopressors and Inotropes for Patients in Shock.Journal of Intensive Care Medicine 2024 April 14
Diagnosis and Management of Cardiac Sarcoidosis: A Scientific Statement From the American Heart Association.Circulation 2024 April 19
Essential thrombocythaemia: A contemporary approach with new drugs on the horizon.British Journal of Haematology 2024 April 9
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app