*2.6. Data Analysis*

Data were summarized by descriptive analysis. Means and SD were calculated for continuous variables, while absolute values and frequency (percentage) were calculated for categorical variables. The assessment of the significance of the results obtained was performed with repeated-measures 1-way ANOVA with "MSS" (MSS-0, MSS-12, and MSS-24) as a within-subject factor. To test the predictive value of PRIS on ΔMSS-24(%) as well as of

the PRIS parameters we used linear regression analysis. Analysis of dependent variable ΔMSS-24 was performed with independent 1-way ANOVA considering the stratification of patients according to the PRIS value as a between-subject independent variable (PRIS ≥ 80; 80 > PRIS ≥ 60; 60 > PRIS ≥ 40; PRIS < 40). The level of significance was set at α = 0.05.
