From the abstract: "This study investigated the utility of including teacher-reported callous–unemotional (CU) behaviors in the assessment of disruptive behaviors in school-based research. Participants included 138 first- and second-grade children (68% male; 76% eligible for free or reduced-price lunch; 61% Black, 9% Latinx, 23% White, and 7% multiracial) who completed assessments during the baseline assessment of an intervention study. Results indicated that teachers could distinguish CU from traditional indicators of disruptive behavior, including attention deficit hyperactivity disorder (ADHD) behaviors and conduct problems (CP). When considered alone, there was mixed evidence for the utility of CU behaviors. Although higher levels of CU behaviors explained unique variation in teacher-reported social competence and global impairment, CU behaviors did not explain unique variation in disciplinary infractions, classroom behavior, or academic functioning after accounting for ADHD and CP behaviors. A different pattern of results was evident when CU was considered in conjunction with ADHD and CP behaviors. Latent profile analyses identified three subgroups of participants (i.e., a nondisruptive group, an ADHD group, and a comorbid group, who exhibited elevated levels of ADHD, CP, and CU). Compared to the nondisruptive group, the ADHD group exhibited higher rates of off-task classroom behavior and worse academic functioning. The comorbid group exhibited moderate-to-large differences from both groups on teacher-reported and objective outcomes. The implications of these results are discussed with respect to the potential value of incorporating CU behaviors, which are becoming prominent in clinical psychology and psychiatry, into school-based research and for school psychology practice. (PsycInfo Database Record (c) 2022 APA, all rights reserved)"