ASD Symptom Severity Moderates the Relationship Between Child Externalizing Behavior and Maternal Stress

Background: Children with autism spectrum disorders (ASD) present a greater number of externalizing behaviors than typically-developing (TD) children (Mahan & Matson 2011). These behaviors present unique stressors to mothers of children with ASD (Peters-Scheffer et al. 2012). Mothers have also reported experiencing elevated levels of stress when raising children with severe ASD symptoms compared to mothers of children with low ASD symptomatology (Konstantareas & Papageorgiou 2006). Similar studies suggest that externalizing behaviors in youth with ASD are stronger predictors of maternal stress than ASD symptoms (Peters-Scheffer et al. 2012, Lecavelier & Wiltz 2006). Previous research also suggests that externalizing behavior is more likely to predict maternal stress even when holding the severity of ASD symptoms constant, and that it remains a stronger predictor even when measured alongside other stressful ASD related symptoms (Peters-Scheffer et al. 2012). It is not known, however, whether degree of ASD symptomatology and child externalizing behaviors interact in relation to maternal stress.

Objectives: The present study analyzes whether ASD symptomatology moderates the relationship between child externalizing behaviors and maternal stress.

Methods: Mothers (N = 223) with exactly one child with ASD (age M = 6.74, SD= 2.99; 84% male) completed the Behavioral Assessment System for Children (BASC-2; Reynolds & Kamphaus, 2004) as a measure of externalizing behaviors and the Social Responsiveness Scale-2 (SRS-2; Constantino et al., 2012) to identify the presence and extent of autistic social impairment in the child. Mothers self-reported stress indices via the Parental Stress Index (PSI-4-SF; Abidin 2012).

Results: Total child externalizing behaviors were found to predict maternal stress, particularly in the Difficult Child Subscale of the PSI (𝞫= -.57, p<.001). Moderation analyses revealed that SRS-2 total scores moderated the relationship between child externalizing behaviors and maternal stress (B= -.01, p<.001), such that the relation was strongest when child ASD symptoms were low (B= .66, p<.001; Figure 1). Post-hoc probing indicated that the same pattern of effects was found in all subdomains of externalizing behaviors (hyperactivity, aggression, and conduct problems all B=-.01, p<.02) and with all SRS-2 subscales (all B < -.01, p< .007).

Conclusions: Externalizing behavior in ASD youth was found to predict maternal stress, with a stronger effect seen in children with lower ASD symptomatology. Essentially, the relationship between externalizing behavior and maternal stress was strongest at low levels of ASD symptomatology. It may be that mothers of children with fewer ASD symptoms may attribute parenting stress to child externalizing behaviors, whereas mothers of those with high ASD symptoms may attribute stress to ASD symptoms. Specifically, mothers’ behavioral expectations may differ when perceiving their child’s social ability as greater than other children with ASD (Mori et. al 2009). Subsequently, these expectations may affect mothers’ sense of parenting efficacy, leading to increased stress. The poignant relationship found between externalizing behavior, maternal stress and ASD symptomatology demonstrates a significant need in providing relevant and comprehensive interventions that address all three elements of this model, thereby ameliorating stress levels in mothers and improving family quality of life for families of youth with ASD.