Therefore, all statistical analyses were performed
by external statisticians. Data regarding
study results were screened by a firewall team
consisting of scientists employed by the sponsor,
GlaxoSmithKline Biologicals, who were not involved
in the conduct of the trial, and only data
that would not risk participant- level unblinding
were shared with the authors. (A more detailed
description of the methods that are being used
in the study is provided in the Supplementary