Statistical analysis
A descriptive analysis was performed. Continuous variables are reported as mean and standard deviation or median and range according to their distribution, while categorical variables are presented as counts and percentages. An Excel spreadsheet and STATA version 13 statistical software were used. For the analysis of COVID-19-related mortality in patients diagnosed with leukemia or lymphoma according to the previously defined waves, proportions were compared using the Chi-squared test. Infostat statistical software was used.