How do the measurement properties of the broad-band scales for attention-deficit/hyperactivity disorder in children perform based on the COSMIN guidelines?

This study systematically evaluated the measurement properties of ADHD-relevant subscales (i.e., subscales measuring inattention and/or hyperactivity-impulsivity) embedded within broad-band behavior rating scales for children with ADHD, using the COSMIN methodology. The aim was to provide evidence-based support for clinical screening, co-occurring assessment, and treatment monitoring. Following PRISMA 2020 guidelines, we conducted a systematic literature search across PubMed, Web of Science, Scopus, and ProQuest. Risk of bias and measurement properties were assessed with the COSMIN Risk of Bias Checklist and Updated Criteria for Good Measurement Properties, respectively. Evidence synthesis was performed through an adapted GRADE approach. Thirty-six studies, covering 12 broad-band instruments, were included. The CBCL Attention Problems subscale was rated as "not recommended" due to insufficient cross-cultural validity (high quality evidence). The SDQ Hyperactivity-Inattention subscale demonstrated the most favorable evidence profile, with moderate quality evidence for structural validity and internal consistency, and high quality evidence for cross-cultural validity, reliability, and convergent/discriminant validity. The CADBI Inattention and Hyperactivity/Impulsivity subscales showed high quality evidence for structural and cross-cultural validity, and moderate quality evidence for internal consistency. The FTF Attention and Hyperactive/Impulsive subscales had moderate quality evidence for structural validity and internal consistency. The CABI Attention Deficit and Hyperactivity subscale had high quality evidence for reliability, but low quality evidence for structural validity and internal consistency. The remaining instruments (ANSER-PQ, CBAI, ECI-4, YI-4, DSMD, ABC, CSI-4) had limited or unsatisfactory evidence for their ADHD-related subscales. Among the included broad-band instruments, given the evidence of insufficient cross-cultural validity, applying the COSMIN criteria to the CBCL Attention Problems subscale would lead to a recommendation against its use; users outside North America should be cautious. The SDQ Hyperactivity-Inattention subscale demonstrates comparatively favorable measurement properties, though this does not establish its overall superiority for ADHD assessment. Future studies should evaluate content validity, measurement error, and responsiveness following COSMIN guidelines. PROSPERO (CRD420250655032).