Safety was analyzed in the total vaccinated cohort,
which included all participants who received
at least one dose of HZ/su or placebo. Efficacy
was analyzed in the total vaccinated cohort
and in the modified vaccinated cohort (primary
analysis); in the latter cohort, participants who
did not receive the second dose of vaccine or who
received the diagnosis of herpes zoster within
1 month after the second dose were excluded.
All significance tests were two-tailed; a P value
of 0.05 or less was considered to indicate statistical
significance. All statistical analyses were
performed with the use of SAS software, version
9.2 (SAS Institute), and StatXact software, version
8.1 (Cytel).