Summary of findings 2. Recombinant zoster vaccine versus placebo for preventing herpes zoster in older adults.
| Recombinant zoster vaccine versus placebo for preventing herpes zoster in older adults | ||||||
| Patient or population: healthy older adults aged ≥ 60 years Settings: outpatients Intervention: recombinant zoster vaccine versus placebo | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No. of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Control | Recombinant zoster vaccine versus placebo | |||||
| Incidence of herpes zoster at least 3.2 years follow‐up Clinical or laboratory criteria Follow‐up: mean 3.2 years | 34 per 1000 | 3 per 1000 (2 to 4) | RR 0.08 (0.03 to 0.23) | 22,022 (2 studies) | ⊕⊕⊕⊝ moderate1 | NNTB = 33 |
| Participants with adverse events ‐ death Clinical criteria Follow‐up: mean 3.2 years | 43 per 1000 | 41 per 1000 (36 to 45) | RR 0.94 (0.84 to 1.04) | 29,311 (2 studies) | ⊕⊕⊕⊝ moderate1 | |
| Participants with adverse events ‐ serious adverse events Clinical or laboratory criteria Follow‐up: mean 3.2 years | 130 per 1000 | 126 per 1000 (118 to 133) | RR 0.97 (0.91 to 1.03) | 29,311 (2 studies) | ⊕⊕⊕⊝ moderate1 | |
| Participants with adverse events ‐ any systemic symptom Clinical criteria Follow‐up: mean 30 days | 291 per 1000 | 648 per 1000 (617 to 680) | RR 2.23 (2.12 to 2.34) | 9762 (2 studies) | ⊕⊕⊕⊝ moderate1 | NNTH = 3.0 |
| Participants with adverse events ‐ potential immune‐mediated disease Clinical or laboratory criteria Follow‐up: mean 3.2 years | 13 per 1000 | 12 per 1000 (9 to 14) | RR 0.88 (0.71 to 1.08) | 29,311 (2 studies) | ⊕⊕⊕⊝ moderate1 | |
| Participants with adverse events ‐ any local symptom Clinical criteria Follow‐up: mean 7 days | 117 per 1000 | 807 per 1000 (746 to 873) | RR 6.89 (6.37 to 7.45) | 9769 (2 studies) | ⊕⊕⊕⊝ moderate1 | NNTH = 1.5 |
| Dropouts ‐ did not receive second dose Clinical or laboratory criteria Follow‐up: mean 3.2 years | 40 per 1000 | 50 per 1000 (50 to 50) | RR 1.25 (1.13 to 1.39) | 29,311 (2 studies) | ⊕⊕⊕⊝ moderate1 | NNTH = 100 |
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; NNTB: number needed to treat for an additional beneficial outcome; NNTH: number needed to treat for an additional harmful outcome; RR: risk ratio | ||||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
1Both studies had limitations in study design or execution (allocation concealment, attrition or detection bias).