Edited by: Marek Kowalski
Validation of a questionnaire (CARAT10) to assess rhinitis and asthma in patients with asthma
Version of Record online: 1 FEB 2010
© 2010 John Wiley & Sons A/S
Volume 65, Issue 8, pages 1042–1048, August 2010
How to Cite
Fonseca, J. A., Nogueira-Silva, L., Morais-Almeida, M., Azevedo, L., Sa-Sousa, A., Branco-Ferreira, M., Fernandes, L. and Bousquet, J. (2010), Validation of a questionnaire (CARAT10) to assess rhinitis and asthma in patients with asthma. Allergy, 65: 1042–1048. doi: 10.1111/j.1398-9995.2009.02310.x
- Issue online: 1 JUL 2010
- Version of Record online: 1 FEB 2010
- Accepted for publication 23 November 2009
- questionnaire design;
- validation studies
To cite this article: Fonseca JA, Nogueira-Silva L, Morais-Almeida M, Azevedo L, Sa-Sousa A, Branco-Ferreira M, Fernandes L, Bousquet J. Validation of a questionnaire (CARAT10) to assess rhinitis and asthma in patients with asthma. Allergy 2010; 65: 1042–1048.
Background and aim: The Control of Allergic Rhinitis and Asthma Test (CARAT) was developed to be used in the concurrent management of these diseases, as recommended by the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines. However, it was necessary to statistically identify and remove redundant questions and to evaluate the new version’s factor structure, internal consistency and concurrent validity.
Methods: In this cross-sectional study 193 adults with allergic rhinitis and asthma from 15 outpatient clinics in Portugal were included. The CARAT questionnaire was reduced using descriptive analysis, exploratory factor analysis and internal consistency. Spearman’s correlations were used to compare the CARAT scores with a medical evaluation and other measures of control, including the Asthma Control Questionnaire and symptoms’ visual analogue scales. The performance against physician rating of control was summarized using the area under the curve (AUC) from receiver operating characteristic analysis. In addition, CARAT was compared with the physician’s decision to reduce, maintain or increase treatment.
Results: The reduced version has 10 questions and 2 factors (CARAT10). The Cronbach’s alpha was 0.85. All correlation coefficients of CARAT10 and factors with the different measures of control met the a priori predictions, ranging from 0.58 to 0.79. The AUC was 0.82. For the physician’s decision groups of reduce, maintain or increase treatment, the mean (IC95%) scores of CARAT10 were 24 (21.4;26.6), 21 (19.4;21.9) and 15 (13.6;16.5), respectively.
Conclusion: CARAT10 has high internal consistency and good concurrent validity, making it useful to compare groups in clinical studies.