Murray 2011

Methods	Randomised, double‐blind, placebo‐controlled, age‐stratified study Multicentre at 46 sites in Canada, Germany, Spain, the UK and the US Duration: 182 days post‐vaccination
Participants	11,980 afebrile participants ≥ 60 years of age; no prior receipt of any varicella or zoster vaccine; no intercurrent illness that might interfere with the interpretation of the study or prevent the participant from completion of the study; no immune dysfunction caused by a medical condition; no use of immunosuppressive therapy; no concomitant use of systemic antiviral therapy with activity against herpes viruses Median age in both group was 69 years Female ˜58.7% ˜96.2% white participants
Interventions	1. Zoster vaccine (refrigerated) SC; N = 5983 2. Placebo SC; N = 5997
Outcomes	1 or more serious side effect(s) occurring 26 weeks (182 days) after the vaccination; vaccine‐related serious side effects, death, injection site adverse events, systemic adverse events; rashes and temperature were only reported if they were considered serious
Purpose of the Study	"To evaluate the general safety of zoster vaccine in adults ≥ 60 years old"
Funding sources	Merck Sharp Dohme Corp.
Notes	Non‐serious adverse events were not reported The study reported 1 or more serious side effect(s) occurring 6 weeks (42 days) and 26 weeks (182 days) after vaccination. In our analyses, we included only the data reported for the second monitoring period, i.e. serious adverse event(s) detected at 182 days after vaccination 36 participants discontinued because of adverse events, 27 participants withdrew consent, 75 participants were lost to follow‐up, 7 participants discontinued because of protocol deviation and 2 participants were discontinued following physician's decision (both were in the placebo group) ITT analysis "For all analyses, cross‐treated (i.e. randomised to ZV and received placebo, or randomised to placebo and received ZV) participants were considered according to the vaccine received and not the vaccine assigned"
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not described
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"The ZV and placebo were reconstituted with sterile diluent immediately prior to administration, and were indistinguishable from each other in appearance. Placebo was the vaccine stabiliser of ZV with no live virus."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"An independent data monitoring committee was established for continuous safety oversight during the study"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Clear patient flow
Selective reporting (reporting bias)	Low risk	The serious adverse events that were defined in the methods section were presented in the results
Other bias	Unclear risk	Not described