Control of Allergic Rhinitis and Asthma Test: A systematic review of measurement properties and COSMIN analysis

The Control of Allergic Rhinitis and Asthma Test (CARAT) is a patient‐reported outcome measurement (PROM) assessing the control of asthma and allergic rhinitis (AR) at a 4 week interval. This systematic review aimed to evaluate the measurement properties of CARAT. Following PRISMA and COSMIN guidelines, we searched five bibliographic databases and retrieved studies concerning the development, assessment of properties, validation, and/or cultural adaption of CARAT. The studies' methodological quality, the quality of measurement properties, and the overall quality of evidence were assessed. We performed meta‐analysis of CARAT measurement properties. We included 16 studies. Control of Allergic Rhinitis and Asthma Test displayed sufficient content validity and very good consistency (meta‐analytical Cronbach alpha = 0.83; 95% CI = 0.80–0.86;I (2) = 62.6%). Control of allergic rhinitis and Asthma Test meta‐analytical intraclass correlation coefficient was 0.91 (95% CI = 0.64–0.98;I (2) = 93.7%). It presented good construct validity, especially for correlations with Patient‐reported outcome measures assessing asthma (absolute Spearman correlation coefficients range = 0.67–0.73; moderate quality of evidence), and good responsiveness. Its minimal important difference is 3.5. Overall, CARAT has good internal consistency, reliability, construct validity and responsiveness, despite the heterogeneous quality of evidence. Control of Allergic Rhinitis and Asthma Test can be used to assess the control of asthma and AR. As first of its kind, this meta‐analysis of CARAT measurement properties sets a stronger level of evidence for asthma and/or AR control questionnaires.