Assessing attention-deficit/hyperactivity disorder-related impairment: Differential item functioning based on child demographic characteristics.

Although numerous studies have examined how child demographic characteristics may impact ratings of attention-deficit/hyperactivity disorder (ADHD) symptoms, there is limited research on how these factors are related to ratings of impairment. This study examined child characteristics (assigned sex, age, race, ethnicity) that may affect parent and teacher ratings of ADHD symptom-related impairments in relationships with family and/or teacher, peer relationships, behavior disruption, academic impairment, homework performance, and self-esteem. The study was conducted using independent U.S. national samples of parents (n = 2,075) and teachers (n = 1,070). Informants rated impairments related to inattention and hyperactivity-impulsivity using the ADHD Rating Scale-5. Rasch analyses were used to examine differential item functioning in relation to child characteristics. Separate analyses were conducted for inattention- and hyperactivity-impulsivity-related impairment for both the parent and teacher samples. For teacher ratings, only two items (behavior disruption, homework impairment) demonstrated differential item functioning with intermediate or large effect sizes (≥ .426 logits) in relation to any child characteristic; whereas for parent ratings, all six items displayed differential item functioning with at least intermediate effect sizes in relation to one or more child characteristics. The findings indicated several areas in which child characteristics may have an impact on ratings of ADHD-related impairment, particularly based on parent ratings, which have potential implications for the diagnostic assessment of ADHD and highlight the need for further research. (PsycInfo Database Record (c) 2025 APA, all rights reserved).