Description of the univariate distribution of the categorical or ordinal variables will be realized with a table of frequencies, and in quantitative variables by means of measures of central tendency (mean or median) and dispersion (standard deviation or 95 % confidence intervals). Depending on the normality of the distribution of variables, any comparisons will be assessed by means of parametric tests (T test; Chi2) or non parametric tests (Mann Whitney). To explore relationships between the variables of study, Kolgomorov-Smirnov for the comparison of groups and analysis of regression bivariate, and multivariate (logistic regression), will be conducted.