Caregiver broader autism phenotype does not moderate the effect of early caregiver-mediated support on infant language outcomes.

Researchers studied whether parents' own mild autism-like traits affected how well a parent training program worked for their babies' language development. They found that while babies of parents with fewer autism-like traits generally had better vocabulary growth, the training program helped all babies equally - regardless of whether their parents had more or fewer autism-like traits. This means the program works well for all families.

This secondary analysis examined whether caregivers' broader autism phenotype (BAP) - subclinical autistic features - influenced the effectiveness of the iBASIS caregiver-mediated support program for infant language development. The study analyzed data from infants at higher likelihood of autism who received the intervention between 12-18 months of age. Results showed that while lower caregiver BAP was associated with better infant vocabulary growth overall, it did not moderate the intervention's effectiveness. Both caregivers with higher and lower BAP levels saw equal benefits from the program for their infants' language outcomes compared to controls, indicating the intervention is equally effective regardless of caregiver autistic features.

The iBASIS caregiver-mediated program can be confidently recommended to all families regardless of caregiver autistic traits. Clinicians should not exclude families based on parental BAP characteristics, as the intervention shows equal effectiveness across different caregiver profiles for supporting infant language development.

This was a secondary analysis of existing trial data with unreported sample size. The study relied on parent-reported measures for some outcomes, which may introduce bias. Specific details about intervention duration, intensity, and long-term follow-up were not provided in the abstract.

Caregiver-mediated supports in general have shown mixed evidence for enhancing language outcomes in infants at higher likelihood of autism. While caregivers play a substantial role in caregiver-mediated supports, little is known about whether caregivers' own subclinical autistic features - known as broader autism phenotype (BAP) - may moderate infant language outcomes. In secondary analysis of trial data, we examined whether caregiver BAP moderated the effectiveness of the iBASIS caregiver-mediated support program (received when infants were mean aged 12-18 months) for infant language outcomes (measured on parent-reported and direct assessment of receptive and expressive language). While lower caregiver BAP was linked to increased parent-reported infant vocabulary growth in general terms, it did not actually moderate the effect of the caregiver-mediated support program on those infant language outcomes.

In relative terms therefore, infants of caregivers with both higher and lower BAP benefited equally from this support on parent-report compared to the comparison group. Caregiver BAP is associated with slower vocabulary growth in infants, but caregivers with autistic features can be recommended for this caregiver-mediated video-feedback based program, as their infants benefitted from such support.