However, in case of non-compliance of the assumption of sphericity, the multidimensional approach and the multidimensional variance analysis (MANOVA) were used. Additionally, in case of receiving significant results the analysis of multiple comparisons in pairs (post-hoc tests) was conducted in order to accurately determine which two averages are significantly different from each other. Moreover, in case of significant results, the ɛ2 coefficient, which is the estimator of the variance of the dependent variable (results of the applied questionnaires) explained by the independent variable (intervention – group psychoeducation) in the sample was calculated.