Control of Allergic Rhinitis and Asthma Test for Children (CARATkids): A systematic review and meta-analysis of its measurement properties.

Control of Allergic Rhinitis and Asthma Test for Children (CARATkids) is the first patient-reported outcome measure (PROM) designed to assess both allergic rhinitis and asthma simultaneously in children aged 6 to 12 years. CARATkids has been validated in several languages and countries, highlighting the need for a review of its psychometric properties. This study aims to evaluate the measurement properties of CARATkids. This systematic review follows PRISMA and COSMIN guidelines. A systematic search was performed across three databases (Ovid/MEDLINE, Web of Science, and Scopus in October 2023, updated in June 2025). We included studies focused on the development, cultural adaptation, or validation of CARATkids, as well as studies comparing CARATkids with other PROMs. We evaluated the quality of CARATkids development, the methodological quality of primary studies, the overall rating, and the certainty of evidence for each CARATkids measurement property and performed a meta-analysis of its measurement properties. Our search retrieved 193 results. We included nine studies. CARATkids displayed sufficient content validity. Regarding internal consistency, we found a meta-analytical Cronbach alpha of 0.81 (95% CI = 0.79; 0.83). CARATkids displayed sufficient reliability (meta-analytical intraclass correlation coefficient 0.86 [95% CI = 0.61; 0.96]). The minimal clinically important difference was 2.76. Construct validity had sufficient evidence for most correlations, with absolute meta-analytical Spearman coefficients from 0.37 to 0.71. Responsiveness showed strong correlations between CARATkids and most outcome measurement instruments. These findings support CARATkids as a suitable tool for assessing asthma and allergic rhinitis in children aged 6 to 12 years who present both conditions simultaneously.