3.2.1 Comparison of the baseline characteristics before and after PSM
Baseline characteristics (age, gender, perforation size, malleus handle exposure status, and ABG value for frequencies of 250 Hz to 4000 Hz before surgery) in the TF and FTTC groups were compared; a significant difference was observed in the ABG values at 2000 Hz. However, after PSM, the variables in the two groups were balanced. The differences in the baseline characteristics before and after surgery are shown in Supplementary Table.