Fig 1. Flow chart of the study.
Patients who developed a censuring event during the follow up period contributed to the study until the date of the occurrence of the censoring event.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.