Mediating Factors in Within-Person Developmental Cascades of Externalising, Internalising and ADHD Symptoms in Childhood

Abstract

Previous studies have offered evidence for peer problems and academic achievement as mediators in developmental cascades from externalising to internalising problems, and from ADHD symptoms to both internalising and externalising problems. However, these mediators have not been found to fully account for these cascades, indicating that there may be additional mediators involved. This study investigated the role of harsh parenting and parental involvement alongside academic achievement and peer problems in mediating within-person developmental cascades from externalising to internalising problems and from ADHD symptoms to internalising and externalising problems using autoregressive latent trajectory models with structured residuals. Models were fit for parent- and teacher-reports on children’s psychosocial development as measured by the Social Behaviour Questionnaire (SBQ) collected over ages 7, 9, and 11 in an ethnically diverse Swiss longitudinal cohort study (z-proso; N = 1387, 51% male). Results indicated that, when appropriately disentangling within- from between-person effects, none of the considered factors acted as significant mediators in longitudinal within-person relations between ADHD, internalising and externalising problems; hence, mediating mechanisms in developmental cascades remain to be identified.

Testing for Within × Within and Between × Within Moderation Using Random Intercept Cross-Lagged Panel Models

“…First, the results support prior research finding evidence for developmental cascades from conduct to emotional problems (Capaldi, 1992;Murray et al, 2020). Evidence for cascades in the other direction has been mixed (Carlson & Cantwell, 1980;Speyer et al, 2022), however, findings of the current study suggest that these cascades may be at play during middle childhood.…”

“…Studies have found evidence for developmental cascades from externalising problems to internalising problems (e.g., Murray et al, 2020). However, few studies have tested such cascades within a framework that allows for an appropriate disaggregation of within-person effects (for an example, see Speyer et al, 2022), and no studies have investigated whether the strength of such cascade effects may be affected by continuous moderating factors. In line with a risk-protective model (Rutter, 1979), factors such as cognitive abilities or peer problems may buffer or increase an individual's risk for the development of co-occurring mental health problems.…”

“…If at least three waves of data are available, the RI-CLPM allows for the decomposition of observed data into within-and between-person components, thus ensuring that the cross-lagged effects, under certain assumptions, provide unbiased estimates of within-person effects (Hamaker et al, 2015). Similar to CLPMs, RI-CLPMs can be extended to include mediation (Speyer et al, 2022) or between-person moderation involving categorical variables in multi-group models (Mulder & Hamaker, 2021). However, moderation involving continuous variables, often described as interactions, are less straightforward to implement, for reasons discussed below.…”

Dynamic interplay of developing internalising and externalising mental health from early childhood to mid-adolescence: Teasing apart trait, state, and cross-cohort effects

“…Some early studies have noted no significant predictive effects (also known as cascading effects [ 20 ]) between internalising and externalising mental health in children or adolescents [ 22 – 24 ]. In contrast, other evidence has come to light indicating a unidirectional predictive effect [ 10 , 25 , 26 ].…”

“…The majority of the above studies on the interplay between internalising and externalising mental health symptoms have adopted a state-trait perspective [ 10 , 24 , 26 ], recognising that childhood internalising and externalising mental health symptoms are characterised by both stability and change over time. Hence, it is important to distinguish between inter-individual (also known as between-child) associations from intra-individual (also known as within-child) associations between and within the domains of internalising and externalising symptoms.…”