Treatment Outcomes of Children with Primary Versus Secondary Callous-Unemotional Traits

Objective: Recent efforts to improve outcomes for young children with conduct problems and callous-unemotional (CU) traits involve adapting treatments to meet the unique needs of this subgroup. However, these efforts have ignored accumulating evidence for distinct primary and secondary variants within the CU subgroup. Existing treatment adaptations uniformly target risk factors associated with primary CU traits and no studies have investigated variant-specific patterns of responsiveness to treatment adaptations among young children with CU-type conduct problems. Method: Participants were 45 families with a 3- to 7-year-old clinic-referred child ( M = 4.84 years, SD = 1.08, 84% boys) with conduct problems and CU traits. Primary and secondary CU variants were defined based on baseline parent-rated anxiety scores. All families received Parent-Child Interaction Therapy adapted for CU traits (PCIT-CU) at an urban university-based research clinic. Families completed five assessments measuring child conduct problems and affective outcomes. Results: Linear mixed-effects modeling showed that the rate and shape of change over time in conduct problems differed between variants, such that children with secondary CU traits showed deterioration in defiant and dysregulated behaviors from post-treatment to follow-up, whereas primary CU traits were associated with maintained gains. There were no variant differences in rate of improvement in CU traits. Affective empathy did not improve for either variant. Internalizing problems meaningfully improved by follow-up for children with secondary CU traits. Conclusions: Findings suggest that PCIT-CU is a promising intervention for children with conduct problems and primary CU traits, but may require further personalization for children with secondary CU traits. This trial was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12616000280404).