SPSS 17.0 for Windows (SPSS Inc., Chicago, IL) was used to analyze the data. Descriptive statistics were computed for demographic data, independent variables,
and outcome measures. Wilcoxon-signed rank tests were performed to examine
changes in the children’s emotional functioning and adaptive behaviors, as well as
differences in the level of parental stress. The level of significance was set at p <
.05. An effect size index r was established on the basis of the z score divided by the
square root of the total sample (low effect size: 0.30 > r ≥ 0.10, medium effect size:
0.50 > r ≥ 0.30, large effect size: r ≥ 0.50; Cohen, 1988).