However, it is not clear whether appropriate analyses that take matching into account were utilized in their univariate comparisons, and whether the comparisons displayed in their Table 1 represent univariate or multivariate comparisons. They indicated that they analyzed their data using Fisher's exact test for categorical variables and the Wilcoxon rank-sum test for continuous variables. If the authors did not use matching, would the comparisons in Table 1 have been different if they had? Would this have altered the "significant" risk factors included in the multivariate analysis?