Statistical analyses
Statistical analysis was performed using SPSS software version 25.0 (IBM, Armonk, NY, USA). The normality of the data distribution was analyzed using the Shapiro–Wilk test. To evaluate clinical efficacy of IPL before and after treatment, paired t-test and McNemar's test were performed. Independent t- and chi-squared tests were performed to compare differences in outcomes between the two filters. Mann–Whitney U and Fisher exact tests were used to compare baseline clinical parameters between the responding and non-responding subgroups. A p value of < 0.05 was considered statistically significant.