**3. Statistical analysis**

To achieve the study, we have used individual medical files, and, for instruments of interpreting data, we have used a series of statistic applications including both the descriptive methods and the analytic ones; the data are centralized in the database EXCEL and SPSS and processed with the available statistic functions, compatible and adequate to the type of the collected data (at nominal, regular and reporting level).

The descriptive statistics, the distribution of the frequencies and the comparisons have been done by means of the program SPSS Statistics, ver. 21; the data of the different parameters are presented as average ± standard deviation (SD). The correlations between the parameters, using the correlation coefficients (Pearson, Spearman, and Kendall) have also been evaluated. The comparisons among the groups under study have been made by means of the Student and Anova tests. All of them have been statistically significant at the level of p<sup>1</sup> = 0,05 and p2 = 0,01.
