Fig 1.
CONSORT flowchart of study participants.
Table 1.
Baseline participant’s characteristics.
Fig 2.
Schematic representation of the hypothesized mediation model.
Treatment allocation is a binary variable representing the treatment (coded 1) and control (coded 0) groups. Loadings for the intercept factor were fixed to 1; the first loading for the slope factor was fixed to zero, and the following to 1.2 and 3.6 respecting the laps of time between the observations. The estimated parameter ai and as represent the effect of the treatment on the initial point (intercept, i.e., 6 months) and on the linear rate of change (i.e., increasing or decreasing) over time of the modeled mediator. The parameters bi and bs represent the effect of the mediator (both intercept and growth factors) on the child outcomes. The estimated parameter ‘c’ represents the direct association, i.e., the remaining non-mediated effect. Estimated residual variances for the observed scores are omitted from the figure for clarity.
Fig 3.
Trajectories of home environment dimensions during early childhood for the treatment and control groups.
Blue lines represent the control group, red lines represent the treatment group.
Table 2.
Treatment effect on the latent growth model parameters.
Table 3.
Indirect (mediation) effect of treatment on cognitive and emotional development via changes in home environment.
Fig 4.
Complementary exploratory analyses.
The figure represents the absolute difference in size (y axis; Hedge’s g, >20 = low; 0.20–0.50 = moderate; >0.50 = large) of the indirect effect of each mediator (x axis) between the subgroup defined by the binary moderators (colors), for the 2 outcomes (left, emotional development; right, cognitive development). For example, the indirect effect of variety on internalizing problems is very different for children of younger mothers (< 20 years old) compared to older mothers (> 20 years old).