Statistical methods
postoperative penile edema, hypospadias
Data were coded and entered using the statistical package for the Social Sciences (SPSS) version 26 (IBM Corp., Armonk, NY, USA). Data were summarized using mean, standard deviation, median, minimum and maximum in quantitative data and using frequency (count) and relative frequency (percentage) for categorical data. Comparisons between quantitative variables were done using the non-parametric Mann–Whitney test [Sample size calculation was done using the comparison of the incidence of postoperative penile edema after hypospadias repair between patients treated with local corticosteroids injection and matched non-treated patients. Searching the literature failed to find any previous results that can be used to build up sample size. Therefore, we performed a pilot study of 8 cases in each group to get usable results. According to our pilot study, the incidence of postoperative penile edema in corticosteroid group was 4/8 (50%), while in non-treated group it was 6/8 (75%). Accordingly, we calculated that the minimum proper sample size was 58 participants in each group to be able to reject the null hypothesis with 80% power at α = 0.05 level using Chi squared test. Sample size calculation was done using Stats Direct statistical software version 2.7.2 for MS Windows, StatsDirect Ltd., Cheshire, UK.