Statistical Analysis
Data analyses were examined by using Statistical Package for Social Sciences (SPSS), Version 20.0 for Windows (SPSS Inc., Chicago, IL, USA). The variables were investigated using visual (histograms, probability plots) and analytical methods (Kolmogorov-Simirnov test) whether or not they were normally distributed. Normally distributed variables were presented using means and standard deviations, and non-normaly distributed variables using median and range (maximum and minimum). Comparisions of the groups were performed using the Student t (normally distributed variables) and Mann-Whitney U (non normally distributed variables). The chi-square test was used to analyze of categorical variables. P values <0.05 were considered statistically significant.