The data was stored with double entry on access database and processed by a software developed in R language
and the statistical analysis performed with the Statistical Package for Social Sciences software – SPSS, version 13. The continuous variables depicted by measures of central tendency (mean or median), scatter plot, and of minimum and maximum values. For the comparison of categorical variables, the Fisher’s exact test or they Chi-squared test were used with α = 0.05 for statistical significance and 95% confidence interval.