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.
The marker size indicates the relative weight of the study as it contributes to the results of the overall comparison. IV indicates inverse-variance random-effect analysis. Percentages do not total 100 owing to rounding. HR indicates hazard ratio.
