Statistical analysis
Data collection and statistical analyses were performed using SPSS 22.0 0 (SPSS Statistics UK, SPSS, Chicago, IL, USA). Descriptive statistics were used. For outcome comparison, the Pearson chi-square test or Fisher’s exact test was used for ordinal variables and the independent T-samples test was used for continuous variables. A p-value < 0.05 was considered statistically significant.Due to the skewed distribution of the histogram for the PFDI-20 scores (determined by statistical tests of normality), we have chosen to present the median and interquartile range in the tables rather than the mean scores. This way the impact of outliers is minimalized.More details on the study design and methods can be found in the first publication (the POP-UP study) [