Question normal

First I would thank authors of this well-conducted RCT. They finally provide a clear and strong evidence for a long debating issue.

Second, I have some methodological questions.

A) What is the registry based RCT? It is the first time to know about it.

B) The log-rank test didn't use. Instead, chi-square is the one used. I need explanation, please.

C) In table-1, the median has been used to measure central tendency and IQR to measure the dispersion. Why not mean and SD?

Again I would thank both authors, experts as well as moderator.